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Thomas Reid, Selections from the Scottish Philosophy of Common Sense [1915]

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Thomas Reid, Selections from the Scottish Philosophy of Common Sense, edited, with an introduction by G.A. Johnston (Chicago: Open Court, 1915).

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About this Title:

Johnston introduces his selection of some representative works of the Scottish School of Common Sense by Thomas Reid, Adam Ferguson, James Beattie, and Dugald Stewart.

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The text is in the public domain.

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Table of Contents:

Edition: current; Page: [iii]
The Open Court Series of Classics of Science and Philosophy, No. 2
EDITED, WITH AN INTRODUCTION, BY G. A. JOHNSTON, M.A. lecturer in moral philosophy in the university of glasgow
Edition: current; Page: [iv]

Copyright in Great Britain under the Act of 1911

Edition: current; Page: [v]


  • Introduction . . . . . . page 1
    • I. Introduction to the Philosophy of Common Sense
      • § 1. The Importance of the Subject, and the Means of Prosecuting it . . . . 27
      • § 2. The Impediments to our Knowledge of the Mind . . . . . . 30
    • II. Analysis of a Typical Sensation
      • § 1. The Sensation considered abstractly . . 37
      • § 2. Sensation and Remembrance, Natural Principles of Belief . . . 39
      • § 3. Judgment and Belief in some Cases precede Simple Apprehension . . . 43
      • § 4. Two Theories of the Nature of Belief Refuted 44
      • § 5. Apology for Metaphysical Absurdities—Sensation without a Sentient, a Consequence of the Theory of Ideas . . . . 48
      • § 6. The Conception and Belief of a Sentient Being or Mind is suggested by our Constitution—The Notion of Relations not always got by comparing the Related Ideas . . 56
      • § 7. There is a Quality or Virtue in Bodies, which we call their Smell—How this is connected in the Imagination with the Sensation . 60Edition: current; Page: [vi]
      • § 8. That there is a Principle in Human Nature, from which the Notion of this, as well as all other Natural Virtues or Causes, is derived 63
      • § 9. Whether in Sensation the Mind is Active or Passive? . . . . . 70
    • III. Knowledge and Reality
      • § 1. Of Hardness . . . . . 72
      • § 2. Of Natural Signs . . . . 74
      • § 3. Of Extension . . . . . 80
      • § 4. Of the Visible Appearances of Objects . . 84
      • § 5. Of Perception in General . . . 89
      • § 6. Of the Process of Nature in Perception . . 98
      • Appendix: Of Cause and Power . . . 100
    • IV. The Operations of the Mind
      • § 1. Principles taken for Granted . . . 111
      • § 2. Of Hypotheses and Analogy . . . 117
      • § 3. Of Perception . . . . . 118
      • § 4. Of Sensation . . . . . 122
      • § 5. Of Primary and Secondary Qualities . . 125
      • § 6. Of Conception . . . . . 128
      • § 7. Of Judgment . . . . . 132
      • § 8. Of Common Sense . . . . 148
      • § 9. First Principles of Contingent Truths . . 152
      • § 10. First Principles of Necessary Truths . . 157
    • V. Of Morals
      • § 1. Of Benevolent Affection in General . . 161
      • § 2. There are Rational Principles of Action in Man 165
      • § 3. Of Regard to Our Good on the Whole . . 168
      • § 4. Of the Notion of Duty, Rectitude, Moral Obligation . . . . . . 173
      • § 5. Observations concerning Conscience . . 182
      • § 6. That Moral Approbation implies a Real Judgment . . . . . . 186
    • Of Man’s Progressive Nature . . . 197
    Edition: current; Page: [vii]
    • Of the Perception of Truth in General . 217
    • I. Of the Object of Philosophy, and the Method of Prosecuting Philosophical Inquiries . . . . . . 229
    • II. Of the Association of Ideas . . 233
    • III. Of the Power which the Mind has over the Train of its Thoughts . . . 236
    • IV. Of the Influence of Association on our Active Principles, and on our Moral Judgments . . . . . 242
    • V. Of Certain Laws of Belief, inseparably connected with the Exercise of Consciousness, Memory, Perception, and Reasoning . . . . 249
  • Index . . . . . . . 265
Edition: current; Page: [1]



The Scottish Philosophy of Common Sense originated as a protest against the philosophy of the greatest Scottish philosopher. Hume’s sceptical conclusions did not excite as much opposition as might have been expected. But in Scotland especially there was a good deal of spoken criticism which was never written; and some who would have liked to denounce Hume’s doctrines in print were restrained by the salutary reflection that if they were challenged to give reasons for their criticism they would find it uncommonly difficult to do so. Hume’s scepticism was disliked, but it was difficult to see how it could be adequately met.

At this point Reid1 stepped into the field. He Edition: current; Page: [2] was the only man of his time who really understood the genesis of Hume’s scepticism and succeeded in locating its sources. At first sight it would seem that this discovery required no peculiar perspicuity. It would seem that nobody could help seeing that Hume’s sceptical conclusions were based on Locke’s premises, and that Hume could never be successfully opposed by any critic who accepted Locke’s assumptions. But this is precisely one of those obvious things that is noticed by nobody. And in fact Reid was the first man to see it clearly. It thus became his duty to question the assumptions on which all his own early thought had been based. The result of this reflection was the conclusion that, since the “ideal theory” of Locke and Edition: current; Page: [3] Berkeley logically led to Hume’s scepticism, and since scepticism was intolerable, that theory would have to be amended, or, if necessary, abandoned.

Reid himself gives an admirable account of the way in which he was roused from his dogmatic slumbers. “I acknowledge,” he says in the Dedication of the Inquiry, “that I never thought of calling in question the principles commonly received with regard to the human understanding, until the Treatise of Human Nature was published in the year 1739. The ingenious author of that treatise upon the principles of Locke—who was no sceptic—hath built a system of scepticism, which leaves no ground to believe any one thing rather than its contrary. His reasoning appeared to me to be just; there was therefore a necessity to call in question the principles upon which it was founded, or to admit the conclusion.”1 Reid was determined not to acquiesce in the sceptical conclusion. And that for three reasons. Scepticism, he says, is trebly destructive. It destroys the science of a philosopher, it undermines the faith of a Christian, and it renders nugatory the prudence of a man of common understanding. Thus he was forced to undertake a criticism of the assumptions on which that sceptical conclusion was based. “For my own satisfaction, I entered into a serious examination of the principles upon which this sceptical Edition: current; Page: [4] system is built; and was not a little surprised to find that it leans with its whole weight upon a hypothesis which is ancient indeed, and hath been very generally received by philosophers, but of which I could find no solid proof.”1 This hypothesis is to be found in Locke and Descartes, and consists in the postulation of a world of ideas intermediate between the knower and the object known. It is from this hypothesis, says Reid, that Hume’s scepticism directly results. Reid therefore really criticises Hume via Locke. He takes up the position that if Locke’s assumption be proved untenable, Hume’s conclusion will fall to the ground. Thus, while it is true that it was Hume who elicited Reid’s philosophy, that philosophy is not so much a direct “answer to Hume” as an answer to Locke.

Now, Locke’s doctrine admitted of two, and only two, answers. One of these was given by Berkeley, and led to the scepticism of Hume. The other was given by Reid. For Locke perception involves three elements: the percipient, the idea perceived, and the thing; and it is assumed that the idea is somehow a copy of the external reality. Both Berkeley and Reid saw clearly the difficulties of the doctrine of Representative Perception. If the mind is confined to its own ideas and is cut off from immediate knowledge of the real world, how is it to know if its ideas do or do not agree with things? Edition: current; Page: [5] In order to compare two things, it is necessary to know both. Thus we cannot compare ideas with the things which they represent, because we can never escape the circle of our own ideas. And the further objection is advanced that if the external world does exist, it cannot be like our ideas, for nothing but an idea can be like an idea. Both Berkeley and Reid saw these difficulties in Locke’s doctrine. They both agreed that Locke had gone wrong. How he had gone wrong was the question on which they differed. They agreed, it is true, that Locke had obscured the nature of knowledge by interpolating a spurious factor. But they differed toto cœlo with regard to the question which of Locke’s factors was unreal. By Berkeley it was maintained that Locke’s third factor—the material world—had no real existence. But Reid denied the existence of Locke’s second factor. Locke’s imitative and intermediate ideas are simply creatures of phantasy: they have no real existence. Thus Berkeley is left with mind plus ideas, and Reid with mind plus matter. For both, the relation between mind and its object is immediate.

Reid naturally regarded his own answer to Locke as better than Berkeley’s, partly because Hume had argued that Berkeley’s criticisms of Locke’s material substance could with equal force be levelled against Berkeley’s own spiritual substance; and partly because he believed that a world which Edition: current; Page: [6] consists of minds plus matter is more “consentaneous” with common sense than one which contains only minds plus ideas. Neither of these reasons, in point of fact, is sound, though both would have been perfectly valid if Berkeley had really meant what Hume and Reid thought that he meant. It ought to be remembered, when Reid is criticised for his vulgar failure to appreciate the point of Berkeley’s argument, that Hume also did not fully understand it. Berkeley takes special pains in the Three Dialogues between Hylas and Philonous to answer precisely the criticisms that Reid and Hume advanced. He points out, for instance, that his arguments against material substance cannot be successfully used against spiritual substances, for spirits are not inert and passive, but are active beings, which are not known as ideas, but are apprehended through notions. Hume’s criticism of Berkeley simply makes the unjustifiable assumption that spirits are on the same level as ideas, and that they are known in the same way. Reid’s misapprehension of Berkeley’s meaning is neither more nor less egregious. He assumes that in denying the existence of matter, and in asserting that the world consists solely of spirits and ideas, Berkeley is proclaiming the non-existence of the world to which common sense bears testimony. Now, Reid knew that Berkeley was never weary of insisting that his doctrine Edition: current; Page: [7] denied nothing that common sense admitted. The material world which Berkeley destroyed was not a conviction of common sense, but a philosophical hypothesis. For him the world remained as real as ever. If Hume and Reid had been less eager to criticise Berkeley and more anxious to understand him, they might have seen the importance of the suggestions made by him—e.g. in the second edition of the Principles and in Siris—towards an interpretation of the world based on the concurrence of both reason and sense. Hume entirely failed to appreciate Berkeley’s suggestions towards a notional system of knowledge, and, if Reid noticed them, he made no use of them in the development of his own system.

The great merit of Reid’s answer to Locke lay in its immunity from criticism along Hume’s lines. By denying the existence of ideas in Locke’s sense, it entirely cut the ground away from Hume. Reid himself points out that his own doctrine, in one aspect, forms the reductio ad absurdum of the whole “ideal theory.” Locke starts with minds, ideas, and matter. Berkeley disproves matter and retains minds and ideas. Hume denies the existence of minds and preserves only ideas. And Reid in turn denies ideas. Thus the development of thought has, by a necessary process, led to the destruction of the whole apparatus with which Locke started. Reid therefore resolves to begin Edition: current; Page: [8] afresh, not with hypotheses postulated by philosophy, but with principles guaranteed by common sense.

It may have been noticed that in this account of the development of Reid’s thought with reference to his immediate predecessors, two slightly different views have been implied. So far these have purposely not been distinguished. For it is probable that the actual development of Reid’s own views was determined in the way sketched above, partly by direct opposition to Hume and partly by criticism of Locke. It is probable that he was not clearly conscious how far his views owed their origin to criticism of Locke, and how far to antagonism to Hume. But it is worth while to make the difference clear. If we regard Reid’s doctrine as developed mainly by criticism of Locke’s assumptions, it can be shewn that it retains more of the Descartes-Locke assumptions than it denies. In particular, Reid preserves, though he restates, the two-substance doctrine, which was one of the most important elements in the Locke-Descartes Gemeingut. In one aspect, then, Reid may be regarded as Locke purged and Locke re-created. It is only a mild exaggeration to say that Reid’s system is a critical reconstruction of Locke.

But when Reid’s work is considered in its direct application to Hume, it assumes a somewhat different tinge. It then appears more closely Edition: current; Page: [9] related to the uncritical appeals to common sense made by Reid’s contemporaries and successors. Reid saw that some of Hume’s conclusions were ridiculous, and he believed that others were impious; and he was apt to assume that their apparent absurdity and impiety supplied adequate grounds for denying them. Reid appealed from the hypotheses of philosophy to the “principles of common sense.” Common sense secured to him the belief in the existence of mind and matter. From this naïve dualism was developed his Natural Realism. Such is another view that may be taken of the genesis of Reid’s doctrine.

The truth lies somewhere between the two sharply contrasted views. The distinction between them was almost certainly hardly present to Reid’s own mind. But the former is nearer the truth than the latter. It cannot be denied that there is a Reid who in the Inquiry and even in the Essays appeals from philosophy, in the manner of Beattie and Oswald, to vulgar common sense. There is a Reid who condemns a theory by consigning its author to the mad-house. There is a Reid who gets rid of difficulties by simply laughing at them. But this is not the normal Reid. When the normal Reid appeals to common sense, it is an appeal not to blind feeling, but to permanent principles of human nature. He makes an appeal, as Sir William Hamilton has said, “from the heretical Edition: current; Page: [10] conclusions of particular philosophies to the catholic principles of all philosophy.”1 Further, while it is perfectly true that Reid’s nisus to independent philosophical inquiry was due to his desire to rebut Hume’s conclusions, and while he did criticise Hume directly, he had acuteness enough to see that the only really successful criticism of Hume must be Higher Criticism, in the strict sense of that much-abused term, i.e. criticism higher upstream, nearer the source.

Reid’s work was both constructive and critical. He did not start absolutely de novo with the convictions of common sense. What he did was to take over, in large measure, the results of Locke’s work, at the same time subjecting it to examination in the light of all the information he could himself acquire by a common-sense investigation of mental processes. Nothing could be truer than Sidgwick’s statement, “If Locke is the first founder of the distinctively British science, Empirical Psychology, of which the primary method is introspective observation and analysis, I think Reid has a fair claim to be regarded as a second founder.”2

Much less favourable was the judgment that Kant passed on Reid. In the Prolegomena to Any Future Metaphysic, Kant declares that Reid entirely missed the point of Hume’s problem. What Reid ought to have done, says Kant, was to “probe Edition: current; Page: [11] more deeply into the nature of reason.” But, instead of doing this, he “discovered a more convenient means of putting on a bold face without any proper insight into the question, by appealing to the common sense of mankind.” Such an appeal to common sense, Kant continues, had the effect of enabling the emptiest babbler without an atom of insight to attack with some show of success a thinker of Hume’s calibre. Now, it seems inconceivable that, if Kant had really read Reid, he could have written about him in such a strain. And it has been suggested that in all probability Kant had no first - hand knowledge of Reid. In the Prolegomena he mentions Reid along with Oswald, Beattie, and Priestley, making no distinction between them. But if Kant had himself read the writings of these men, he could hardly have bracketed them, for Reid is altogether in a different class from the other three. Hence the very plausible suggestion, supported by the way in which Kant mentions the names (“Reid, Oswald, Beattie, and even Priestley”), that Kant’s knowledge of Reid was derived solely from the criticisms in Priestley’s Examination.

But Hume had certainly read Reid, and it is interesting to compare his criticism with Kant’s. Hume received, from a common friend (Dr Blair), parts of the manuscript of Reid’s Inquiry. He started to read it with no enthusiasm, muttering a Edition: current; Page: [12] wish “that the parsons would confine themselves to their old task of worrying one another, and leave philosophers to argue with moderation, temper, and good manners.” But the book itself entirely dissolved Hume’s prejudice, and elicited a generous and appreciative letter to Reid. “It is certainly very rare,” Hume writes, “that a piece so deeply philosophical is wrote with so much spirit, and affords so much entertainment to the reader. . . . There are some objections that I would propose, but I will forbear till the whole can be before me. I will only say that if you have been able to clear up these abstruse and important topics, instead of being mortified, I shall be so vain as to pretend to a share of the praise.” The point specially worth noticing in this testimony is the fact that Hume remarks on the “deeply philosophical” character of Reid’s work. He does not dream of talking of “empty babblers”: in particular, it does not occur to him that Reid had appealed from scientific philosophy to vulgar common sense. He recognises that Reid’s attack on him is a damaging criticism, made on the strictly philosophical level.

The analogies between Reid’s work and Kant’s are many and striking. Reid began, as Kant did, by comparing the slow progress made by philosophy with the rapid advance of physical science. And, like Kant, Reid determined that, if philosophy Edition: current; Page: [13] were to advance, the attitude of physical science must be adopted. Like Kant, Reid was a competent mathematician and physicist, with a great respect for Newton. But his general philosophical method differs from that of Kant. While Kant’s work is written, in the main, from the epistemological standpoint, Reid remains true to the traditional British psychological method. The philosopher must undertake an examination of the operations of the mind. He is an anatomist of the mind. His task is much more difficult than that of the student of the anatomy of the body, “for it is his own mind only that he can examine with any degree of accuracy and distinctness.”1 Philosophy is based on the results of our introspective observation of the working of our own minds.

Reid’s critique of knowledge, like Kant’s, opposes any sensationalism such as Hume’s. Hume maintained that the mind and its objects can be reduced to a series of particular sensations, and that these individual sensations may be known, each independent of the other. Reid criticises this view, to which he gives the scholastic name “simple apprehension.” It is a mistake to think, he says, that knowledge consists originally in simple apprehension.2 It is a mistake to think that we start originally with simple sensations and then refer them to their subjects and their objects. On the contrary, Edition: current; Page: [14] the simplest act of the mind is already a judgment. Judgment is both logically and psychologically prior to simple apprehension. Judgment is the unit of knowledge. By a process of analysis, it is possible to differentiate elements within the judgment. But these elements are elements merely; and they can be regarded separately only by a process of abstraction. Thus even simple apprehension is not really simple: it is reached by abstraction from the natural unit of knowledge. If we analyse even the simplest sensation, we find that it always implies judgment.

In the Inquiry Reid proves this in detail, by an examination of the five external senses. He begins with smell, the simplest and least intellectual of these, and shows that even here a system of natural judgments is suggested. These natural judgments are not actually given in experience: they are suggested by experience. The natural judgments thus suggested are necessary for the constitution of experience. Were sense-experience not accompanied by these natural suggestions, it would itself be an impossibility. What are these constitutive natural judgments? There is the judgment, in the first place, of existence. Our sensations immediately suggest that what we now feel or perceive actually exists, and memory suggests that what we remember did actually exist. But this judgment of existence does not mean that what we feel exists Edition: current; Page: [15] only as a sensation. It implies the permanent existence of (a) minds and (b) the material world. Reid admits that we cannot logically infer the existence either of minds or of the external world. But he insists that they are principles of common sense, “They are judgments of nature—judgments not got by comparing ideas and perceiving agreements and disagreements, but immediately inspired by our constitution.”1

Another natural judgment is that there is a real difference between primary and secondary qualities. Reid points out that Berkeley’s arguments against the distinction must be regarded as conclusive by all who agree with the “ideal theory.” “Yet, after all,” he says, “there appears to be a real foundation for it in the principles of our nature.”2 He draws a sharp distinction between sensible qualities and sensations. The almost universal tendency to confuse the external quality with the sensation is due to the fact that we have no name for the sensation, as distinct from the perceived quality. But Reid insists that, though we draw no distinction in language, the distinction does really exist. For example, our sensation of hardness is quite distinct from the hardness which really exists in bodies. “Hitherto, they have been confounded by the most acute enquirers into the principles of human nature, although they appear, Edition: current; Page: [16] upon accurate reflection, not only to be different things, but as unlike as pain is to the point of a sword.”1 In every case the sensible quality must be distinguished from the sensation; and in no case is the sensible quality dependent for its existence on the sensation. Reid really obscures the distinction between primary and secondary qualities, though in a different way from Berkeley. Berkeley had reduced all qualities to secondary qualities: Reid, in effect, makes all qualities primary. Thus colour means, he says, “not a sensation of the mind, which can have no existence when it is not perceived, but a quality or modification of bodies, which continues to be the same, whether it is seen or not.”2 Eventually, after considering in detail in the Inquiry various primary and secondary qualities, the only difference Reid finds between them is that there is a resemblance and a necessary connection between primary qualities and the sensations we have of them, but not between secondary qualities and our sensations. In the Essays Reid attacks the problem again, and adds that our senses give us a direct and distinct notion of primary qualities, but of secondary qualities only a relative and obscure notion. The important point is not so much Reid’s attempt to distinguish primary from secondary qualities as his insistence on the fact that in both cases our Edition: current; Page: [17] sensations are generically different from the qualities of things. Hence mere sensation can never give us knowledge of an object: for that, perception is necessary. Reid is far from consistent in maintaining the distinction between perception and sensation; but in the main he holds that while sensation is the condition of perception, yet bare sensation by itself neither is an object of knowledge nor can give complete knowledge of an object. In all knowledge, he holds, is involved the perceptual activity of the self, working in accordance with certain natural judgments. It will be evident how far this theory is in general agreement with Kant’s doctrine of the importance of judgment, and the indispensability for knowledge of the subject with its categories.

Reid’s contemporaries and successors in the Scottish School made little, if any, real contribution to the Philosophy of Common Sense. He was the greatest, as he was the first, of the School; and its other members were content, for the most part, to repeat in other words what he had already said. Reid was the most strictly philosophical member of the school. The extracts in this volume, though they reveal the other thinkers at their best, make that sufficiently clear.

Beattie1 in his own day far surpassed Reid in reputation: this was largely due to what may now Edition: current; Page: [18] be regarded as his most serious defects, the lack of “body” in his work, and his vulgar denunciations of Hume. Beattie’s popularity in his own day had a good deal to do, as Stewart points out, with the bad odour in which the Philosophy of Common Sense came to be held. Beattie was regarded as its chief exponent, and his uncritical work was considered typical of the Scottish philosophy. His Essay on the Nature and Immutability of Truth is a rather foolish and vulgar attack on Hume’s scepticism, but it was appreciated more than Reid’s work by those who, like George III., were not peculiarly intelligent.

Ferguson’s1 work betrays the same thinness and Edition: current; Page: [19] lack of originality as Beattie’s. He himself describes his Principles of Moral and Political Science as “much of what everybody knows about mind.” At the same time, it must be remembered that it was he who promulgated the “perfectibilianism” which had a considerable vogue at the time as an ethical theory.

Stewart1 gave a very clear and scholarly restatement of the principles of the Common-Sense Philosophy. A man of great erudition and much personal charm, and easily the foremost philosopher of the day in Britain, he did more than anyone else not merely to popularise that philosophy, but to secure for it the respectful, and, in some cases, the admiring, attention of other philosophers. His rechauffé of Reid is often overburdened with illustration and analogy. But there are points on which he states the common views of the school in a more Edition: current; Page: [20] systematic and thorough way than Reid. In particular may be mentioned the sections on Taste, which show æsthetic appreciation and real originality, and the chapter on the “Fundamental Laws of Human Belief,” which contains a fresh restatement of the “principles of common sense.”

Other representatives of the Philosophy of Common Sense are Campbell and Oswald. George Campbell (1719-1796), one of the original members of Reid’s “Wise Club,” incorporated his contributions to the society in his Philosophy of Rhetoric (1776). James Oswald published in 1766-1772 An Appeal to Common Sense in behalf of Religion, a popular vindication of religion and morality. They simply follow Reid, and apply his views without making any real contributions to the Philosophy of Common Sense. Like his contemporaries, Lord Monboddo (1714-1799) was opposed to the Locke - Berkeley - Hume development of thought, but he did not agree with Reid that its sceptical conclusions could be met by an appeal to common sense. In his Antient Metaphysics he advocated a “return to Plato” as the only means of defeating scepticism. Thomas Brown (1778-1820) and Sir William Hamilton (1788-1856) are sometimes classed with the common-sense philosophers; but they both abandoned many of its most important positions. Brown’s philosophy has interest now mainly as an anticipation of the association Edition: current; Page: [21] psychology, and almost everything he added to the Scottish philosophy was inconsistent with it. Sir William Hamilton was much influenced by German philosophy, especially that of Kant. His “Natural Realism” is a strange mixture of Reid and Kant, and he should not be regarded as a representative of the Philosophy of Common Sense.

In Reid’s followers the weaknesses and defects of the Scottish philosophy emerge with special clearness, but even in Reid himself they are sufficiently noticeable. As they are so obvious, it is the less necessary to labour them. But three or four of them may be simply mentioned. The Scottish philosophers are apt to turn, in difficulties, to vulgar, uncritical common sense. They are apt to set up an opposition between philosophy and common sense, and to appeal from the verdict of philosophy to the bar of common sense. They are apt to regard as the principles of common sense simply those principles which to them seem to be self-evident. Again, they are too ready to acquiesce in the ultimate inexplicability of their principles. No attempt is made to prove or deduce the system of natural judgments. There seems to be no reason why there should be so many and no more. In the works of all the representatives of the school, again and again one meets with assertions of the final inability of philosophy to explain the why and wherefore of things. Further, they are very careless Edition: current; Page: [22] in the use of terms. While it is of fundamental importance for the school to distinguish between perception and sensation, and while every one of the writers does distinguish between them officially, they often use the terms indiscriminately and ambiguously. Perception and conception are often confused, and also conception and imagination. The school does have a definite terminology, but too often it uses its terms loosely.

The historical significance of the Philosophy of Common Sense is considerable. In England and Germany it has never been much appreciated, but in France it has exercised a great influence. Royer-Collard (1763-1845) introduced it to his country-men, and, through his great pupil Victor Cousin (1792-1867), made it the greatest power in the French philosophy of the period. Cousin’s work was supported by Jouffroy (1796-1842), who translated Reid’s works into French. For half a century the Philosophy of Common Sense was the dominant philosophy in the American Universities, and it is to the Scottish President of an American College that we owe the most comprehensive study of it. In recent years in France there has been a recrudescence of interest in the Scottish philosophy, an interest which has extended to the writings of Professor S. S. Laurie, who, in several able works, attempted what amounts to a critical reconstruction of the traditional Scottish Natural Realism.

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The selections in this volume are reprinted from the following editions:—

Reid’s Works, edited by Sir William Hamilton, sixth edition, 1863.

Beattie’s Essay on the Nature and Immutability of Truth, seventh edition, 1807.

Ferguson’s Principles of Moral and Political Science, 1792.

Stewart’s Collected Works, edited by Sir William Hamilton, 1854-1858.

The following books may be consulted:—

J. M‘Cosh, The Scottish Philosophy, London, 1875.

A. S. Pringle - Pattison, Scottish Philosophy, fourth edition, Edinburgh, 1907.

H. Laurie, Scottish Philosophy in its National Development, Glasgow, 1902.

A. Campbell Fraser, Thomas Reid, Edinburgh, 1898.

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§ 1.: The Importance of the Subject, and the Means of Prosecuting It

The fabric of the human mind is curious and wonderful, as well as that of the human body. The faculties of the one are with no less wisdom adapted to their several ends than the organs of the other. Nay, it is reasonable to think, that, as the mind is a nobler work and of a higher order than the body, even more of the wisdom and skill of the divine Architect hath been employed in its structure. It is, therefore, a subject highly worthy of inquiry on its own account, but still more worthy on account of the extensive influence which the knowledge of it hath over every other branch of science.

In the arts and sciences which have least connection with the mind, its faculties are the engines which we must employ; and the better we understand their nature and use, their defects and Edition: current; Page: [28] disorders, the more skilfully we shall apply them, and with the greater success. But in the noblest arts, the mind is also the subject upon which we operate. The painter, the poet, the actor, the orator, the moralist, and the statesman, attempt to operate upon the mind in different ways, and for different ends; and they succeed according as they touch properly the strings of the human frame. Nor can their several arts ever stand on a solid foundation, or rise to the dignity of science, until they are built on the principles of the human constitution.

Wise men now agree, or ought to agree, in this, that there is but one way to the knowledge of nature’s works—the way of observation and experiment. By our constitution, we have a strong propensity to trace particular facts and observations to general rules, and to apply such general rules to account for other effects, or to direct us in the production of them. This procedure of the understanding is familiar to every human creature in the common affairs of life, and it is the only one by which any real discovery in philosophy can be made.

The man who first discovered that cold freezes water, and that heat turns it into vapour, proceeded on the same general principles, and in the same method by which Newton discovered the law of gravitation and the properties of light. His Edition: current; Page: [29] regulæ philosophandi are maxims of common sense, and are practised every day in common life; and he who philosophizes by other rules, either concerning the material system or concerning the mind, mistakes his aim.

Conjectures and theories are the creatures of men, and will always be found very unlike the creatures of God. If we would know the works of God, we must consult themselves with attention and humility, without daring to add anything of ours to what they declare. A just interpretation of nature is the only sound and orthodox philosophy: whatever we add of our own is apocryphal, and of no authority.

All our curious theories of the formation of the earth, of the generation of animals, of the origin of natural and moral evil, so far as they go beyond a just induction from facts, are vanity and folly, no less than the Vortices of Des Cartes, or the Archæus of Paracelsus. Perhaps the philosophy of the mind hath been no less adulterated by theories, than that of the material system. The theory of Ideas is indeed very ancient, and hath been very universally received; but, as neither of these titles can give it authenticity, they ought not to screen it from a free and candid examination; especially in this age, when it hath produced a system of scepticism that seems to triumph over all science, and even over the dictates of common sense.

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All that we know of the body, is owing to anatomical dissection and observation, and it must be by an anatomy of the mind that we can discover its powers and principles.

§ 2.: The Impediments to our Knowledge of the Mind

But it must be acknowledged, that this kind of anatomy is much more difficult than the other; and, therefore, it needs not seem strange that mankind have made less progress in it. To attend accurately to the operations of our minds, and make them an object of thought, is no easy matter even to the contemplative, and to the bulk of mankind is next to impossible.

An anatomist who hath happy opportunities, may have access to examine with his own eyes, and with equal accuracy, bodies of all different ages, sexes, and conditions; so that what is defective, obscure, or preternatural in one, may be discerned clearly and in its most perfect state in another. But the anatomist of the mind cannot have the same advantage. It is his own mind only that he can examine with any degree of accuracy and distinctness. This is the only subject he can look into. He may, from outward signs, collect the operations of other minds; but these signs are for the most part ambiguous, and must be interpreted by what he perceives within himself.

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So that, if a philosopher could delineate to us, distinctly and methodically, all the operations of the thinking principle within him, which no man was ever able to do, this would be only the anatomy of one particular subject; which would be both deficient and erroneous, if applied to human nature in general. For a little reflection may satisfy us, that the difference of minds is greater than that of any other beings which we consider as of the same species.

Of the various powers and faculties we possess, there are some which nature seems both to have planted and reared, so as to have left nothing to human industry. Such are the powers which we have in common with the brutes, and which are necessary to the preservation of the individual, or the continuance of the kind. There are other powers, of which nature hath only planted the seeds in our minds, but hath left the rearing of them to human culture. It is by the proper culture of these that we are capable of all those improvements in intellectuals, in taste, and in morals, which exalt and dignify human nature; while, on the other hand, the neglect or perversion of them makes its degeneracy and corruption.

The two-legged animal that eats of nature’s dainties, what his taste or appetite craves, and satisfies his thirst at the crystal fountain, who propagates his kind as occasion and lust prompt, Edition: current; Page: [32] repels injuries, and takes alternate labour and repose, is, like a tree in the forest, purely of nature’s growth. But this same savage hath within him the seeds of the logician, the man of taste and breeding, the orator, the statesman, the man of virtue, and the saint; which seeds, though planted in his mind by nature, yet, through want of culture and exercise, must lie for ever buried, and be hardly perceivable by himself or by others.

The lowest degree of social life will bring to light some of those principles which lay hid in the savage state; and, according to his training, and company, and manner of life, some of them, either by their native vigour, or by the force of culture, will thrive and grow up to great perfection, others will be strangely perverted from their natural form, and others checked, or perhaps quite eradicated.

This makes human nature so various and multiform in the individuals that partake of it, that, in point of morals and intellectual endowments, it fills up all that gap which we conceive to be between brutes and devils below, and the celestial orders above; and such a prodigious diversity of minds must make it extremely difficult to discover the common principles of the species.

The language of philosophers, with regard to the original faculties of the mind, is so adapted to the prevailing system, that it cannot fit any other; like a coat that fits the man for whom it was made, Edition: current; Page: [33] and shews him to advantage, which yet will sit very awkward upon one of a different make, although perhaps as handsome and as well proportioned. It is hardly possible to make any innovation in our philosophy concerning the mind and its operations, without using new words and phrases, or giving a different meaning to those that are received—a liberty which, even when necessary, creates prejudice and misconstruction, and which must wait the sanction of time to authorize it; for innovations in language, like those in religion and government, are always suspected and disliked by the many, till use hath made them familiar, and prescription hath given them a title.

If the original perceptions and notions of the mind were to make their appearance single and unmixed, as we first received them from the hand of nature, one accustomed to reflection would have less difficulty in tracing them; but before we are capable of reflection, they are so mixed, compounded, and decompounded, by habits, associations, and abstractions, that it is hard to know what they were originally. The mind may, in this respect, be compared to an apothecary or a chemist, whose materials indeed are furnished by nature; but, for the purposes of his art, he mixes, compounds, dissolves, evaporates, and sublimes them, till they put on a quite different appearance; so that it is very difficult to know what they were at first, and Edition: current; Page: [34] much more to bring them back to their original and natural form. And this work of the mind is not carried on by deliberate acts of mature reason, which we might recollect, but by means of instincts, habits, associations, and other principles, which operate before we come to the use of reason; so that it is extremely difficult for the mind to return upon its own footsteps, and trace back those operations which have employed it since it first began to think and to act.

Could we obtain a distinct and full history of all that hath past in the mind of a child, from the beginning of life and sensation, till it grows up to the use of reason—how its infant faculties began to work, and how they brought forth and ripened all the various notions, opinions, and sentiments which we find in ourselves when we come to be capable of reflection—this would be a treasure of natural history, which would probably give more light into the human faculties, than all the systems of philosophers about them since the beginning of the world. But it is in vain to wish for what nature has not put within the reach of our power. Reflection, the only instrument by which we can discern the powers of the mind, comes too late to observe the progress of nature, in raising them from their infancy to perfection.

It must therefore require great caution, and great application of mind, for a man that is grown up Edition: current; Page: [35] in all the prejudices of education, fashion, and philosophy, to unravel his notions and opinions, till he find out the simple and original principles of his constitution, of which no account can be given but the will of our Maker. This may be truly called an analysis of the human faculties; and, till this is performed, it is in vain we expect any just system of the mind—that is, an enumeration of the original powers and laws of our constitution, and an explication from them of the various phænomena of human nature.1

Des Cartes, Malebranche, and Locke, have all employed their genius and skill to prove the existence of a material world; and with very bad success. Poor untaught mortals believe undoubtedly that there is a sun, moon, and stars; an earth, which we inhabit; country, friends, and relations, which we enjoy; land, houses, and moveables, which we possess. But philosophers, pitying the credulity of the vulgar, resolve to have no faith but what is founded upon reason. They apply to philosophy to furnish them with reasons for the belief of those things which all mankind have believed, without being able to give any reason for it. And surely one would expect, that, in matters of such importance, the proof would not be difficult: but it is the most difficult thing in the world. For these three great men, with the best good will, Edition: current; Page: [36] have not been able, from all the treasures of philosophy, to draw one argument that is fit to convince a man that can reason, of the existence of any one thing without him. Admired Philosophy! daughter of light! parent of knowledge and wisdom! if thou art she, surely thou hast not yet arisen upon the human mind, nor blessed us with more of thy rays than are sufficient to shed a darkness visible upon the human faculties, and to disturb that repose and security which happier mortals enjoy, who never approached thine altar, nor felt thine influence! But if, indeed, thou hast not power to dispel these clouds and phantoms which thou hast discovered or created, withdraw this penurious and malignant ray; I despise Philosophy, and renounce its guidance—let my soul dwell with Common Sense.1

It may be observed, that the defects and blemishes in the received philosophy concerning the mind, which have most exposed it to the contempt and ridicule of sensible men, have chiefly been owing to this—that the votaries of this Philosophy, from a natural prejudice in her favour, have endeavoured to extend her jurisdiction beyond its just limits, and to call to her bar the dictates of Common Sense. But these decline this jurisdiction; they disdain the trial of reasoning, and disown its authority; they neither claim its aid, nor dread its attacks.

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In this unequal contest betwixt Common Sense and Philosophy, the latter will always come off both with dishonour and loss; nor can she ever thrive till this rivalship is dropt, these encroachments given up, and a cordial friendship restored: for, in reality, Common Sense holds nothing of Philosophy, nor needs her aid. But, on the other hand, Philosophy (if I may be permitted to change the metaphor) has no other root but the principles of Common Sense; it grows out of them, and draws its nourishment from them.1


§ 1.: The Sensation considered abstractly

Let us now attend carefully to what the mind is conscious of when we smell a rose or a lily; and, since our language affords no other name for this sensation, we shall call it a smell or odour, carefully excluding from the meaning of those names everything but the sensation itself, at least till we have examined it.

Suppose a person who never had this sense before, to receive it all at once, and to smell a rose—can he perceive any similitude or agreement between the smell and the rose? or indeed between it and any other object whatsoever? Certainly he cannot. He finds himself affected in a new way, Edition: current; Page: [38] he knows not why or from what cause. Like a man that feels some pain or pleasure formerly unknown to him, he is conscious that he is not the cause of it himself; but cannot, from the nature of the thing, determine whether it is caused by body or spirit, by something near, or by something at a distance. It has no similitude to anything else, so as to admit of a comparison; and, therefore, he can conclude nothing from it, unless, perhaps, that there must be some unknown cause of it.

It is evidently ridiculous to ascribe to it figure, colour, extension, or any other quality of bodies. He cannot give it a place, any more than he can give a place to melancholy or joy; nor can he conceive it to have any existence, but when it is smelled. So that it appears to be a simple and original affection or feeling of the mind, altogether inexplicable and unaccountable. It is, indeed, impossible that it can be in any body: it is a sensation, and a sensation can only be in a sentient thing.

The various odours have each their different degrees of strength or weakness. Most of them are agreeable or disagreeable; and frequently those that are agreeable when weak, are disagreeable when stronger. When we compare different smells together, we can perceive very few resemblances or contrarieties, or, indeed, relations of any kind between them. They are all so simple in themselves, and so different from each other, that it is Edition: current; Page: [39] hardly possible to divide them into genera and species. Most of the names we give them are particular; as the smell of a rose, of a jessamine, and the like. Yet there are some general names—as sweet, stinking, musty, putrid, cadaverous, aromatic. Some of them seem to refresh and animate the mind, others to deaden and depress it.

§ 2.: Sensation and Remembrance, Natural Principles of Belief

So far we have considered this sensation abstractly. Let us next compare it with other things to which it bears some relation. And first I shall compare this sensation with the remembrance, and the imagination of it.

I can think of the smell of a rose when I do not smell it; and it is possible that when I think of it, there is neither rose nor smell anywhere existing. But when I smell it, I am necessarily determined to believe that the sensation really exists. This is common to all sensations, that, as they cannot exist but in being perceived, so they cannot be perceived but they must exist. I could as easily doubt of my own existence, as of the existence of my sensations. Even those profound philosophers who have endeavoured to disprove their own existence, have yet left their sensations to stand upon their own bottom, stript of a subject, rather than call in question the reality of their existence.

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Here, then, a sensation, a smell for instance, may be presented to the mind three different ways: it may be smelled, it may be remembered, it may be imagined or thought of. In the first case, it is necessarily accompanied with a belief of its present existence; in the second, it is necessarily accompanied with a belief of its past existence; and in the last, it is not accompanied with belief at all, but is what the logicians call a simple apprehension.

Why sensation should compel our belief of the present existence of the thing, memory a belief of its past existence, and imagination no belief at all, I believe no philosopher can give a shadow of reason, but that such is the nature of these operations: they are all simple and original, and therefore inexplicable acts of the mind.

Suppose that once, and only once, I smelled a tuberose in a certain room, where it grew in a pot, and gave a very grateful perfume. Next day I relate what I saw and smelled. When I attend as carefully as I can to what passes in my mind in this case, it appears evident that the very thing I saw yesterday, and the fragrance I smelled, are now the immediate objects of my mind, when I remember it. Further, I can imagine this pot and flower transported to the room where I now sit, and yielding the same perfume. Here likewise it appears, that the individual thing which I saw and smelled, is the object of my imagination.

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Philosophers indeed tell me, that the immediate object of my memory and imagination in this case, is not the past sensation, but an idea of it, an image, phantasm, or species, of the odour I smelled: that this idea now exists in my mind, or in my sensorium; and the mind, contemplating this present idea, finds it a representation of what is past, or of what may exist; and accordingly calls it memory, or imagination. This is the doctrine of the ideal philosophy; which we shall not now examine, that we may not interrupt the thread of the present investigation. Upon the strictest attention, memory appears to me to have things that are past, and not present ideas, for its object. We shall afterwards examine this system of ideas, and endeavour to make it appear, that no solid proof has ever been advanced of the existence of ideas; that they are a mere fiction and hypothesis, contrived to solve the phænomena of the human understanding; that they do not at all answer this end; and that this hypothesis of ideas or images of things in the mind, or in the sensorium, is the parent of those many paradoxes so shocking to common sense, and of that scepticism which disgrace our philosophy of the mind, and have brought upon it the ridicule and contempt of sensible men.

In the meantime, I beg leave to think, with the vulgar, that, when I remember the smell of the tuberose, that very sensation which I had yesterday, Edition: current; Page: [42] and which has now no more any existence, is the immediate object of my memory; and when I imagine it present, the sensation itself, and not any idea of it, is the object of my imagination. But, though the object of my sensation, memory, and imagination, be in this case the same, yet these acts or operations of the mind are as different, and as easily distinguishable, as smell, taste, and sound. I am conscious of a difference in kind between sensation and memory, and between both and imagination. I find this also, that the sensation compels my belief of the present existence of the smell, and memory my belief of its past existence. There is a smell, is the immediate testimony of sense; there was a smell, is the immediate testimony of memory. If you ask me, why I believe that the smell exists, I can give no other reason, nor shall ever be able to give any other, than that I smell it. If you ask, why I believe that it existed yesterday, I can give no other reason but that I remember it.

Sensation and memory, therefore, are simple, original, and perfectly distinct operations of the mind, and both of them are original principles of belief. Imagination is distinct from both, but is no principle of belief. Sensation implies the present existence of its object, memory its past existence, but imagination views its object naked, and without any belief of its existence or non-existence, and is therefore what the schools call Simple Apprehension.

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§ 3.: Judgment and Belief in some Cases precede Simple Apprehension

But here, again, the ideal system comes in our way: it teaches us that the first operation of the mind about its ideas, is simple apprehension—that is, the bare conception of a thing without any belief about it: and that, after we have got simple apprehensions, by comparing them together, we perceive agreements or disagreements between them; and that this perception of the agreement or disagreement of ideas is all that we call belief, judgment, or knowledge. Now, this appears to me to be all fiction, without any foundation in nature; for it is acknowledged by all, that sensation must go before memory and imagination; and hence it necessarily follows, that apprehension, accompanied with belief and knowledge, must go before simple apprehension, at least in the matters we are now speaking of. So that here, instead of saying that the belief or knowledge is got by putting together and comparing the simple apprehensions, we ought rather to say that the simple apprehension is performed by resolving and analysing a natural and original judgment. And it is with the operations of the mind, in this case, as with natural bodies, which are, indeed, compounded of simple principles or elements. Nature does not exhibit these elements separate, to be compounded by us; Edition: current; Page: [44] she exhibits them mixed and compounded in concrete bodies, and it is only by art and chemical analysis that they can be separated.

§ 4.: Two Theories of the Nature of Belief Refuted—Conclusions from what hath been said

But what is this belief or knowledge which accompanies sensation and memory? Every man knows what it is, but no man can define it. Does any man pretend to define sensation, or to define consciousness? It is happy, indeed, that no man does. And if no philosopher had endeavoured to define and explain belief, some paradoxes in philosophy, more incredible than ever were brought forth by the most abject superstition or the most frantic enthusiasm, had never seen the light. Of this kind surely is that modern discovery of the ideal philosophy, that sensation, memory, belief, and imagination, when they have the same object, are only different degrees of strength and vivacity in the idea. Suppose the idea to be that of a future state after death: one man believes it firmly—this means no more than that he hath a strong and lively idea of it; another neither believes nor disbelieves—that is, he has a weak and faint idea. Suppose, now, a third person believes firmly that there is no such thing, I am at a loss to know whether his idea be faint or lively: if it is faint, then there may be a Edition: current; Page: [45] firm belief where the idea is faint; if the idea is lively, then the belief of a future state and the belief of no future state must be one and the same. The same arguments that are used to prove that belief implies only a stronger idea of the object than simple apprehension, might as well be used to prove that love implies only a stronger idea of the object than indifference. And then what shall we say of hatred, which must upon this hypothesis be a degree of love, or a degree of indifference? If it should be said, that in love there is something more than an idea—to wit, an affection of the mind—may it not be said with equal reason, that in belief there is something more than an idea—to wit, an assent or persuasion of the mind?

But perhaps it may be thought as ridiculous to argue against this strange opinion, as to maintain it. Indeed, if a man should maintain that a circle, a square, and a triangle differ only in magnitude, and not in figure, I believe he would find nobody disposed either to believe him or to argue against him; and yet I do not think it less shocking to common sense, to maintain that sensation, memory, and imagination differ only in degree, and not in kind. I know it is said, that, in a delirium, or in dreaming, men are apt to mistake one for the other. But does it follow from this, that men who are neither dreaming nor in a delirium cannot distinguish them? But how does a man know that he is not in a delirium? Edition: current; Page: [46] I cannot tell: neither can I tell how a man knows that he exists. But, if any man seriously doubts whether he is in a delirium, I think it highly probable that he is, and that it is time to seek for a cure, which I am persuaded he will not find in the whole system of logic.

I mentioned before Locke’s notion of belief or knowledge; he holds that it consists in a perception of the agreement or disagreement of ideas; and this he values himself upon as a very important discovery.

We shall have occasion afterwards to examine more particularly this grand principle of Locke’s philosophy, and to shew that it is one of the main pillars of modern scepticism, although he had no intention to make that use of it. At present let us only consider how it agrees with the instances of belief now under consideration; and whether it gives any light to them. I believe that the sensation I have exists; and that the sensation I remember does not now exist, but did exist yesterday. Here, according to Locke’s system, I compare the idea of a sensation with the ideas of past and present existence: at one time I perceive that this idea agrees with that of present existence, but disagrees with that of past existence; but, at another time, it agrees with the idea of past existence, and disagrees with that of present existence. Truly these ideas seem to be very capricious Edition: current; Page: [47] in their agreements and disagreements. Besides, I cannot, for my heart, conceive what is meant by either. I say a sensation exists, and I think I understand clearly what I mean. But you want to make the thing clearer, and for that end tell me, that there is an agreement between the idea of that sensation and the idea of existence. To speak freely, this conveys to me no light, but darkness; I can conceive no otherwise of it, than as an odd and obscure circumlocution. I conclude, then, that the belief which accompanies sensation and memory, is a simple act of the mind, which cannot be defined. It is, in this respect, like seeing and hearing, which can never be so defined as to be understood by those who have not these faculties; and to such as have them, no definition can make these operations more clear than they are already. In like manner, every man that has any belief—and he must be a curiosity that has none—knows perfectly what belief is, but can never define or explain it. I conclude, also, that sensation, memory, and imagination, even where they have the same object, are operations of a quite different nature, and perfectly distinguishable by those who are sound and sober. A man that is in danger of confounding them, is indeed to be pitied; but whatever relief he may find from another art, he can find none from logic or metaphysic. I conclude further, that it is no less a part of the human Edition: current; Page: [48] constitution, to believe the present existence of our sensations, and to believe the past existence of what we remember, than it is to believe that twice two make four. The evidence of sense, the evidence of memory, and the evidence of the necessary relations of things, are all distinct and original kinds of evidence, equally grounded on our constitution: none of them depends upon, or can be resolved into another. To reason against any of these kinds of evidence is absurd; nay, to reason for them is absurd. They are first principles; and such fall not within the province of reason, but of common sense.

§ 5.: Apology for Metaphysical Absurdities—Sensation without a Sentient, a Consequence of the Theory of Ideas—Consequences of this Strange Opinion

Having considered the relation which the sensation of smelling bears to the remembrance and imagination of it, I proceed to consider what relation it bears to a mind, or sentient principle. It is certain, no man can conceive or believe smelling to exist of itself, without a mind, or something that has the power of smelling, of which it is called a sensation, an operation, or feeling. Yet, if any man should demand a proof that sensation cannot be without a mind or sentient being, I confess that I can give none; and that to pretend to prove it, seems to me almost as absurd as to deny it.

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This might have been said without any apology before the Treatise of Human Nature appeared in the world. For till that time, no man, as far as I know, ever thought either of calling in question that principle, or of giving a reason for his belief of it. Whether thinking beings were of an ethereal or igneous nature, whether material or immaterial, was variously disputed; but that thinking is an operation of some kind of being or other, was always taken for granted, as a principle that could not possibly admit of doubt.

However, since the author above mentioned, who is undoubtedly one of the most acute metaphysicians that this or any other age hath produced, hath treated it as a vulgar prejudice, and maintained that the mind is only a succession of ideas and impressions without any subject; his opinion, however contrary to the common apprehensions of mankind, deserves respect. I beg therefore, once for all, that no offence may be taken at charging this or other metaphysical notions with absurdity, or with being contrary to the common sense of mankind. No disparagement is meant to the understandings of the authors or maintainers of such opinions. Indeed, they commonly proceed, not from defect of understanding, but from an excess of refinement; the reasoning that leads to them often gives new light to the subject, and shews real genius and deep penetration in the author; Edition: current; Page: [50] and the premises do more than atone for the conclusion.

If there are certain principles, as I think there are, which the constitution of our nature leads us to believe, and of which we are under a necessity to take for granted in the common concerns of life, without being able to give a reason for them—these are what we call the principles of common sense; and what is manifestly contrary to them, is what we call absurd.

Indeed, if it is true, and to be received as a principle of philosophy, that sensation and thought may be without a thinking being, it must be acknowledged to be the most wonderful discovery that this or any other age hath produced. The received doctrine of ideas is the principle from which it is deduced, and of which indeed it seems to be a just and natural consequence. And it is probable, that it would not have been so late a discovery, but that it is so shocking and repugnant to the common apprehensions of mankind, that it required an uncommon degree of philosophical intrepidity to usher it into the world. It is a fundamental principle of the ideal system, that every object of thought must be an impression or an idea—that is, a faint copy of some preceding impression. This is a principle so commonly received, that the author above mentioned, although his whole system is built upon it, never offers the least proof of it. It is upon this Edition: current; Page: [51] principle, as a fixed point, that he erects his metaphysical engines, to overturn heaven and earth, body and spirit. And, indeed, in my apprehension, it is altogether sufficient for the purpose. For, if impressions and ideas are the only objects of thought, then heaven and earth, and body and spirit, and everything you please, must signify only impressions and ideas, or they must be words without any meaning. It seems, therefore, that this notion, however strange, is closely connected with the received doctrine of ideas, and we must either admit the conclusion, or call in question the premises.

Ideas seem to have something in their nature unfriendly to other existences. They were first introduced into philosophy, in the humble character of images or representatives of things; and in this character they seemed not only to be inoffensive, but to serve admirably well for explaining the operations of the human understanding. But, since men began to reason clearly and distinctly about them, they have by degrees supplanted their constituents, and undermined the existence of everything but themselves. First, they discarded all secondary qualities of bodies; and it was found out by their means, that fire is not hot, nor snow cold, nor honey sweet; and, in a word, that heat and cold, sound, colour, taste, and smell, are nothing but ideas or impressions. Bishop Berkeley advanced Edition: current; Page: [52] them a step higher, and found out, by just reasoning from the same principles, that extension, solidity, space, figure, and body, are ideas, and that there is nothing in nature but ideas and spirits. But the triumph of ideas was completed by the Treatise of Human Nature, which discards spirits also, and leaves ideas and impressions as the sole existences in the universe. What if, at last, having nothing else to contend with, they should fall foul of one another, and leave no existence in nature at all? This would surely bring philosophy into danger; for what should we have left to talk or to dispute about?

However, hitherto these philosophers acknowledge the existence of impressions and ideas; they acknowledge certain laws of attraction, or rules of precedence, according to which, ideas and impressions range themselves in various forms, and succeed one another: but that they should belong to a mind, as its proper goods and chattels, this they have found to be a vulgar error. These ideas are as free and independent as the birds of the air, or as Epicurus’s atoms when they pursued their journey in the vast inane. Shall we conceive them like the films of things in the Epicurean system?

  • Principio hoc dico, rerum simulacra vagari,
  • Multa modis multis, in cunctas undique parteis
  • Tenuia, quæ facile inter se junguntur in auris,
  • Obvia cum veniunt.
  • Lucr.
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Or do they rather resemble Aristotle’s intelligible species, after they are shot forth from the object, and before they have yet struck upon the passive intellect? But why should we seek to compare them with anything, since there is nothing in nature but themselves? They make up the whole furniture of the universe; starting into existence, or out of it, without any cause; combining into parcels, which the vulgar call minds; and succeeding one another by fixed laws, without time, place, or author of those laws.

Yet, after all, these self-existent and independent ideas look pitifully naked and destitute, when left thus alone in the universe, and seem, upon the whole, to be in a worse condition than they were before. Des Cartes, Malebranche, and Locke, as they made much use of ideas, treated them handsomely, and provided them in decent accommodation; lodging them either in the pineal gland, or in the pure intellect, or even in the divine mind. They moreover clothed them with a commission, and made them representatives of things, which gave them some dignity and character. But the Treatise of Human Nature, though no less indebted to them, seems to have made but a bad return, by bestowing upon them this independent existence; since thereby they are turned out of house and home, and set adrift in the world, without friend or connection, without a rag to cover their nakedness; and who Edition: current; Page: [54] knows but the whole system of ideas may perish by the indiscreet zeal of their friends to exalt them?

However this may be, it is certainly a most amazing discovery that thought and ideas may be without any thinking being—a discovery big with consequences which cannot easily be traced by those deluded mortals who think and reason in the common track. We were always apt to imagine, that thought supposed a thinker, and love a lover, and treason a traitor: but this, it seems, was all a mistake; and it is found out that there may be treason without a traitor, and love without a lover, laws without a legislator, and punishment without a sufferer, succession without time, and motion without anything moved, or space in which it may move: or if, in these cases, ideas are the lover, the sufferer, the traitor, it were to be wished that the author of this discovery had farther condescended to acquaint us whether ideas can converse together, and be under obligations of duty or gratitude to each other; whether they can make promises and enter into leagues and covenants, and fulfil or break them, and be punished for the breach. If one set of ideas makes a covenant, another breaks it, and a third is punished for it, there is reason to think that justice is no natural virtue in this system.

It seemed very natural to think that the Treatise Edition: current; Page: [55] of Human Nature required an author, and a very ingenious one too; but now we learn that it is only a set of ideas which came together and arranged themselves by certain associations and attractions.

After all, this curious system appears not to be fitted to the present state of human nature. How far it may suit some choice spirits, who are refined from the dregs of common sense, I cannot say. It is acknowledged, I think, that even these can enter into this system only in their most speculative hours, when they soar so high in pursuit of those self-existent ideas as to lose sight of all other things. But when they condescend to mingle again with the human race, and to converse with a friend, a companion, or a fellow-citizen, the ideal system vanishes; common sense, like an irresistible torrent, carries them along; and, in spite of all their reasoning and philosophy, they believe their own existence, and the existence of other things.

Indeed, it is happy they do so; for, if they should carry their closet belief into the world, the rest of mankind would consider them as diseased, and send them to an infirmary. Therefore, as Plato required certain previous qualifications of those who entered his school, I think it would be prudent for the doctors of this ideal philosophy to do the same, and to refuse admittance to every man who is so weak as to imagine that he ought to have the same belief in solitude and in company, Edition: current; Page: [56] or that his principles ought to have any influence upon his practice; for this philosophy is like a hobby-horse, which a man in bad health may ride in his closet, without hurting his reputation; but, if he should take him abroad with him to church, or to the exchange, or to the play-house, his heir would immediately call a jury, and seize his estate.

§ 6.: The Conception and Belief of a Sentient Being or Mind is suggested by our Constitution—The Notion of Relations not always got by comparing the Related Ideas

Leaving this philosophy, therefore, to those who have occasion for it, and can use it discreetly as a chamber exercise, we may still inquire how the rest of mankind, and even the adepts themselves, except in some solitary moments, have got so strong and irresistible a belief, that thought must have a subject, and be the act of some thinking being; how every man believes himself to be something distinct from his ideas and impressions—something which continues the same identical self when all his ideas and impressions are changed. It is impossible to trace the origin of this opinion in history; for all languages have it interwoven in their original construction. All nations have always believed it. The constitution of all laws and governments, as well as the common transactions of life, suppose it.

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It is no less impossible for any man to recollect when he himself came by this notion; for, as far back as we can remember, we were already in possession of it, and as fully persuaded of our own existence, and the existence of other things, as that one and one make two. It seems, therefore, that this opinion preceded all reasoning, and experience, and instruction; and this is the more probable, because we could not get it by any of these means. It appears, then, to be an undeniable fact, that, from thought or sensation, all mankind, constantly and invariably, from the first dawning of reflection, do infer a power or faculty of thinking, and a permanent being or mind to which that faculty belongs; and that we as invariably ascribe all the various kinds of sensation and thought we are conscious of, to one individual mind or self.

But by what rules of logic we make these inferences, it is impossible to shew; nay, it is impossible to shew how our sensations and thoughts can give us the very notion and conception either of a mind or of a faculty. The faculty of smelling is something very different from the actual sensation of smelling; for the faculty may remain when we have no sensation. And the mind is no less different from the faculty; for it continues the same individual being when that faculty is lost. Yet this sensation suggests to us both a faculty and a mind; and not only suggests the notion of them, Edition: current; Page: [58] but creates a belief of their existence; although it is impossible to discover, by reason, any tie or connection between one and the other.

What shall we say, then? Either those inferences which we draw from our sensations—namely, the existence of a mind, and of powers or faculties belonging to it—are prejudices of philosophy or education, mere fictions of the mind, which a wise man should throw off as he does the belief of fairies; or they are judgments of nature—judgments not got by comparing ideas, and perceiving agreements and disagreements, but immediately inspired by our constitution.

If this last is the case, as I apprehend it is, it will be impossible to shake off those opinions, and we must yield to them at last, though we struggle hard to get rid of them. And if we could, by a determined obstinacy, shake off the principles of our nature, this is not to act the philosopher, but the fool or the madman. It is incumbent upon those who think that these are not natural principles, to shew, in the first place, how we can otherwise get the notion of a mind and its faculties; and then to shew how we come to deceive ourselves into the opinion that sensation cannot be without a sentient being.

It is the received doctrine of philosophers, that our notions of relations can only be got by comparing the related ideas: but, in the present case, Edition: current; Page: [59] there seems to be an instance to the contrary. It is not by having first the notions of mind and sensation, and then comparing them together, that we perceive the one to have the relation of a subject or substratum, and the other that of an act or operation: on the contrary, one of the related things—to wit, sensation—suggests to us both the correlate and the relation.

I beg leave to make use of the word suggestion, because I know not one more proper, to express a power of the mind, which seems entirely to have escaped the notice of philosophers, and to which we owe many of our simple notions which are neither impressions nor ideas, as well as many original principles of belief. I shall endeavour to illustrate, by an example, what I understand by this word. We all know, that a certain kind of sound suggests immediately to the mind, a coach passing in the street; and not only produces the imagination, but the belief, that a coach is passing. Yet there is here no comparing of ideas, no perception of agreements or disagreements, to produce this belief; nor is there the least similitude between the sound we hear and the coach we imagine and believe to be passing.

It is true that this suggestion is not natural and original; it is the result of experience and habit. But I think it appears, from what hath been said, that there are natural suggestions: particularly, Edition: current; Page: [60] that sensation suggests the notion of present existence, and the belief that what we perceive or feel does now exist; that memory suggests the notion of past existence, and the belief that what we remember did exist in time past; and that our sensations and thoughts do also suggest the notion of a mind, and the belief of its existence, and of its relation to our thoughts. By a like natural principle it is, that a beginning of existence, or any change in nature, suggests to us the notion of a cause and compels our belief of its existence. And, in like manner, as shall be shewn when we come to the sense of touch, certain sensations of touch, by the constitution of our nature, suggest to us extension, solidity, and motion, which are nowise like to sensations, although they have been hitherto confounded with them.

§ 7.: There is a Quality or Virtue in Bodies, which we call their Smell—How this is connected in the Imagination with the Sensation

We have considered smell as signifying a sensation, feeling, or impression upon the mind; and in this sense, it can only be in a mind, or sentient being: but it is evident that mankind give the name of smell much more frequently to something which they conceive to be external, and to be a quality of body: they understand something by it which Edition: current; Page: [61] does not at all infer a mind; and have not the least difficulty in conceiving the air perfumed with aromatic odours in the deserts of Arabia, or in some uninhabited island, where the human foot never trod. Every sensible day-labourer hath as clear a notion of this, and as full a conviction of the possibility of it, as he hath of his own existence; and can no more doubt of the one than of the other.

Suppose that such a man meets with a modern philosopher, and wants to be informed what smell in plants is. The philosopher tells him, that there is no smell in plants, nor in anything but in the mind; that it is impossible there can be smell but in a mind; and that all this hath been demonstrated by modern philosophy. The plain man will, no doubt, be apt to think him merry: but, if he finds that he is serious, his next conclusion will be that he is mad; or that philosophy, like magic, puts men into a new world, and gives them different faculties from common men. And thus philosophy and common sense are set at variance. But who is to blame for it? In my opinion the philosopher is to blame. For if he means by smell, what the rest of mankind most commonly mean, he is certainly mad. But if he puts a different meaning upon the word, without observing it himself, or giving warning to others, he abuses language and disgraces philosophy, without doing any service to truth: as if a man should exchange the meaning Edition: current; Page: [62] of the words daughter and cow, and then endeavour to prove to his plain neighbour, that his cow is his daughter, and his daughter his cow.

I believe there is not much more wisdom in many of those paradoxes of the ideal philosophy, which to plain sensible men appear to be palpable absurdities, but with the adepts pass for profound discoveries. I resolve, for my own part, always to pay a great regard to the dictates of common sense, and not to depart from them without absolute necessity: and, therefore, I am apt to think that there is really something in the rose or lily, which is by the vulgar called smell, and which continues to exist when it is not smelled: and shall proceed to inquire what this is; how we come by the notion of it; and what relation this quality or virtue of smell hath to the sensation which we have been obliged to call by the same name, for want of another.

Let us therefore suppose, as before, a person beginning to exercise the sense of smelling; a little experience will discover to him, that the nose is the organ of this sense, and that the air, or something in the air, is a medium of it. And finding, by farther experience, that, when a rose is near, he has a certain sensation, when it is removed, the sensation is gone, he finds a connection in nature betwixt the rose and this sensation. The rose is considered as a cause, occasion, or antecedent of the sensation; the sensation as an effect or consequence of the Edition: current; Page: [63] presence of the rose; they are associated in the mind, and constantly found conjoined in the imagination.

But here it deserves our notice, that, although the sensation may seem more closely related to the mind its subject, or to the nose its organ, yet neither of these connections operate so powerfully upon the imagination as its connection with the rose its concomitant. The reason of this seems to be, that its connection with the mind is more general, and noway distinguisheth it from other smells, or even from tastes, sounds, and other kinds of sensations. The relation it hath to the organ is likewise general, and doth not distinguish it from other smells; but the connection it hath with the rose is special and constant; by which means they become almost inseparable in the imagination, in like manner as thunder and lightning, freezing and cold.

§ 8.: That there is a Principle in Human Nature, from which the Notion of this, as well as all other Natural Virtues or Causes, is derived

In order to illustrate further how we come to conceive a quality or virtue in the rose which we call smell, and what this smell is, it is proper to observe, that the mind begins very early to thirst after principles which may direct it in the exertion Edition: current; Page: [64] of its powers. The smell of a rose is a certain affection or feeling of the mind; and, as it is not constant, but comes and goes, we want to know when and where we may expect it; and are uneasy till we find something which, being present, brings this feeling along with it, and, being removed, removes it. This, when found, we call the cause of it; not in a strict and philosophical sense, as if the feeling were really effected or produced by that cause, but in a popular sense; for the mind is satisfied if there is a constant conjunction between them; and such causes are in reality nothing else but laws of nature. Having found the smell thus constantly conjoined with the rose, the mind is at rest, without inquiring whether this conjunction is owing to a real efficiency or not; that being a philosophical inquiry, which does not concern human life. But every discovery of such a constant conjunction is of real importance in life, and makes a strong impression upon the mind.

So ardently do we desire to find everything that happens within our observation thus connected with something else as its cause or occasion, that we are apt to fancy connections upon the slightest grounds; and this weakness is most remarkable in the ignorant, who know least of the real connections established in nature. A man meets with an unlucky accident on a certain day of the year, and, knowing no other cause of his misfortune, he is apt Edition: current; Page: [65] to conceive something unlucky in that day of the calendar; and, if he finds the same connection hold a second time, is strongly confirmed in his superstition. I remember, many years ago, a white ox was brought into this country, of so enormous a size that people came many miles to see him. There happened, some months after, an uncommon fatality among women in child-bearing. Two such uncommon events, following one another, gave a suspicion of their connection, and occasioned a common opinion among the country-people that the white ox was the cause of this fatality.

However silly and ridiculous this opinion was, it sprung from the same root in human nature on which all natural philosophy grows—namely, an eager desire to find out connections in things, and a natural, original, and unaccountable propensity to believe that the connections which we have observed in time past will continue in time to come. Omens, portents, good and bad luck, palmistry, astrology, all the numerous arts of divination and of interpreting dreams, false hypotheses and systems, and true principles in the philosophy of nature, are all built upon the same foundation in the human constitution, and are distinguished only according as we conclude rashly from too few instances, or cautiously from a sufficient induction.

As it is experience only that discovers these connections between natural causes and their effects; Edition: current; Page: [66] without inquiring further, we attribute to the cause some vague and indistinct notion of power or virtue to produce the effect. And, in many cases, the purposes of life do not make it necessary to give distinct names to the cause and the effect. Whence it happens, that, being closely connected in the imagination, although very unlike to each other, one name serves for both; and, in common discourse, is most frequently applied to that which, of the two, is most the object of our attention. This occasions an ambiguity in many words, which, having the same causes in all languages, is common to all, and is apt to be overlooked even by philosophers. Some instances will serve both to illustrate and confirm what we have said.

Magnetism signifies both the tendency of the iron towards the magnet, and the power of the magnet to produce that tendency; and, if it was asked, whether it is a quality of the iron or of the magnet, one would perhaps be puzzled at first; but a little attention would discover, that we conceive a power or virtue in the magnet as the cause, and a motion in the iron as the effect; and, although these are things quite unlike, they are so united in the imagination, that we give the common name of magnetism to both. The same thing may be said of gravitation, which sometimes signifies the tendency of bodies towards the earth, sometimes the attractive power of the earth, which we conceive Edition: current; Page: [67] as the cause of that tendency. We may observe the same ambiguity in some of Sir Isaac Newton’s definitions; and that even in words of his own making. In three of his definitions, he explains very distinctly what he understands by the absolute quantity, what by the accelerative quantity, and what by the motive quantity, of a centripetal force. In the first of these three definitions, centripetal force is put for the cause, which we conceive to be some power or virtue in the centre or central body; in the last two, the same word is put for the effect of this cause, in producing velocity, or in producing motion towards that centre.

Heat signifies a sensation, and cold a contrary one; but heat likewise signifies a quality or state of bodies, which hath no contrary, but different degrees. When a man feels the same water hot to one hand and cold to the other, this gives him occasion to distinguish between the feeling and the heat of the body; and, although he knows that the sensations are contrary, he does not imagine that the body can have contrary qualities at the same time. And when he finds a different taste in the same body in sickness and in health, he is easily convinced that the quality in the body called taste is the same as before, although the sensations he has from it are perhaps opposite.

The vulgar are commonly charged by philosophers, with the absurdity of imagining the smell Edition: current; Page: [68] in the rose to be something like to the sensation of smelling; but I think unjustly; for they neither give the same epithets to both, nor do they reason in the same manner from them. What is smell in the rose? It is a quality or virtue of the rose, or of something proceeding from it, which we perceive by the sense of smelling; and this is all we know of the matter. But what is smelling? It is an act of the mind, but is never imagined to be a quality of the mind. Again, the sensation of smelling is conceived to infer necessarily a mind or sentient being; but smell in the rose infers no such thing. We say, this body smells sweet, that stinks; but we do not say, this mind smells sweet and that stinks. Therefore, smell in the rose, and the sensation which it causes, are not conceived, even by the vulgar, to be things of the same kind, although they have the same name.

From what hath been said, we may learn that the smell of a rose signifies two things: First, a sensation, which can have no existence but when it is perceived, and can only be in a sentient being or mind; Secondly, it signifies some power, quality, or virtue, in the rose, or in effluvia proceeding from it, which hath a permanent existence, independent of the mind, and which, by the constitution of nature, produces the sensation in us. By the original constitution of our nature, we are both led to believe that there is a permanent cause of the Edition: current; Page: [69] sensation, and prompted to seek after it; and experience determines us to place it in the rose. The names of all smells, tastes, sounds, as well as heat and cold, have a like ambiguity in all languages; but it deserves our attention, that these names are but rarely, in common language, used to signify the sensations; for the most part, they signify the external qualities which are indicated by the sensations—the cause of which phænomenon I take to be this. Our sensations have very different degrees of strength. Some of them are so quick and lively as to give us a great deal either of pleasure or of uneasiness. When this is the case, we are compelled to attend to the sensation itself, and to make it an object of thought and discourse; we give it a name, which signifies nothing but the sensation; and in this case we readily acknowledge that the thing meant by that name is in the mind only, and not in anything external. Such are the various kinds of pain, sickness, and the sensations of hunger and other appetites. But, where the sensation is not so interesting as to require to be made an object of thought, our constitution leads us to consider it as a sign of something external, which hath a constant conjunction with it; and, having found what it indicates, we give a name to that: the sensation, having no proper name, falls in as an accessory to the thing signified by it, and is confounded under the same name. So that the Edition: current; Page: [70] name may, indeed, be applied to the sensation, but most properly and commonly is applied to the thing indicated by that sensation. The sensations of smell, taste, sound, and colour, are of infinitely more importance as signs or indications, than they are upon their own account; like the words of a language, wherein we do not attend to the sound but to the sense.

§ 9.: Whether in Sensation the Mind is Active or Passive?

There is one inquiry remains, Whether, in smelling, and in other sensations, the mind is active or passive? This possibly may seem to be a question about words, or, at least, of very small importance; however, if it leads us to attend more accurately to the operations of our minds than we are accustomed to do, it is, upon that very account, not altogether unprofitable. I think the opinion of modern philosophers is, that in sensation the mind is altogether passive. And this undoubtedly is so far true, that we cannot raise any sensation in our minds by willing it; and, on the other hand, it seems hardly possible to avoid having the sensation when the object is presented. Yet it seems likewise to be true, that, in proportion as the attention is more or less turned to a sensation or diverted from it, that sensation is more or less perceived and remembered. Every one knows that very intense Edition: current; Page: [71] pain may be diverted by a surprise, or by anything that entirely occupies the mind. When we are engaged in earnest conversation, the clock may strike by us without being heard; at least, we remember not, the next moment, that we did hear it. The noise and tumult of a great trading city is not heard by them who have lived in it all their days; but it stuns those strangers who have lived in the peaceful retirement of the country. Whether, therefore, there can be any sensation where the mind is purely passive, I will not say; but I think we are conscious of having given some attention to every sensation which we remember, though ever so recent.

No doubt, where the impulse is strong and uncommon, it is as difficult to withhold attention as it is to forbear crying out in racking pain, or starting in a sudden fright. But how far both might be attained by strong resolution and practice, is not easy to determine. So that, although the Peripatetics had no good reason to suppose an active and a passive intellect, since attention may be well enough accounted an act of the will, yet I think they came nearer to the truth, in holding the mind to be in sensation partly passive and partly active, than the moderns, in affirming it to be purely passive. Sensation, imagination, memory, and judgment, have, by the vulgar in all ages, been considered as acts of the mind. The manner in Edition: current; Page: [72] which they are expressed in all languages shews this. When the mind is much employed in them, we say it is very active; whereas, if they were impressions only, as the ideal philosophy would lead us to conceive, we ought, in such a case, rather to say, that the mind is very passive; for, I suppose, no man would attribute great activity to the paper I write upon, because it receives variety of characters.

The relation which the sensation of smell bears to the memory and imagination of it, and to a mind or subject, is common to all our sensations, and, indeed, to all the operations of the mind; the relation it bears to the will is common to it with all the powers of understanding; and the relation it bears to that quality or virtue of bodies which it indicates, is common to it with the sensations of taste, hearing, colour, heat, and cold—so that what hath been said of this sense, may easily be applied to several of our senses, and to other operations of the mind; and this, I hope, will apologize for our insisting so long upon it.1


§ 1.: Of Hardness

Hardness of bodies is a thing that we conceive as distinctly, and believe as firmly, as anything in Edition: current; Page: [73] nature. We have no way of coming at this conception and belief, but by means of a certain sensation of touch, to which hardness hath not the least similitude; nor can we, by any rules of reasoning, infer the one from the other. The question is, How we come by this conception and belief?

First, as to the conception: Shall we call it an idea of sensation, or of reflection? The last will not be affirmed; and as little can the first, unless we will call that an idea of sensation which hath no resemblance to any sensation. So that the origin of this idea of hardness, one of the most common and most distinct we have, is not to be found in all our systems of the mind: not even in those which have so copiously endeavoured to deduce all our notions from sensation and reflection.

But, secondly, supposing we have got the conception of hardness, how came we by the belief of it? Is it self-evident, from comparing the ideas, that such a sensation could not be felt, unless such a quality of bodies existed? No. Can it be proved by probable or certain arguments? No; it cannot. Have we got this belief, then, by tradition, by education, or by experience? No; it is not got in any of these ways. Shall we then throw off this belief as having no foundation in reason? Alas! it is not in our power; it triumphs over reason, and laughs at all the arguments of a philosopher. Even Edition: current; Page: [74] the author of the Treatise of Human Nature, though he saw no reason for this belief, but many against it, could hardly conquer it in his speculative and solitary moments; at other times, he fairly yielded to it, and confesses that he found himself under a necessity to do so.

What shall we say, then, of this conception, and this belief, which are so unaccountable and untractable? I see nothing left, but to conclude, that, by an original principle of our constitution, a certain sensation of touch both suggests to the mind the conception of hardness, and creates the belief of it: or, in other words, that this sensation is a natural sign of hardness. And this I shall endeavour more fully to explain.

§ 2.: Of Natural Signs

As in artificial signs there is often neither similitude between the sign and thing signified, nor any connection that arises necessarily from the nature of the things, so it is also in natural signs. The word gold has no similitude to the substance signified by it; nor is it in its own nature more fit to signify this than any other substance; yet, by habit and custom, it suggests this and no other. In like manner, a sensation of touch suggests hardness, although it hath neither similitude to hardness, nor, as far as we can perceive, any necessary connection with it. The difference betwixt these two Edition: current; Page: [75] signs lies only in this—that, in the first, the suggestion is the effect of habit and custom; in the second, it is not the effect of habit, but of the original constitution of our minds.

It appears evident from what hath been said on the subject of language, that there are natural signs as well as artificial; and particularly, that the thoughts, purposes, and dispositions of the mind, have their natural signs in the features of the face, the modulation of the voice, and the motion and attitude of the body: that, without a natural knowledge of the connection between these signs and the things signified by them, language could never have been invented and established among men: and, that the fine arts are all founded upon this connection, which we may call the natural language of mankind. It is now proper to observe, that there are different orders of natural signs, and to point out the different classes into which they may be distinguished, that we may more distinctly conceive the relation between our sensations and the things they suggest, and what we mean by calling sensations signs of external things.

The first class of natural signs comprehends those whose connection with the thing signified is established by nature, but discovered only by experience. The whole of genuine philosophy consists in discovering such connections, and reducing them to general rules. The great Lord Edition: current; Page: [76] Verulam had a perfect comprehension of this, when he called it an interpretation of nature. No man ever more distinctly understood or happily expressed the nature and foundation of the philosophical art. What is all we know of mechanics, astronomy, and optics, but connections established by nature, and discovered by experience or observation, and consequences deduced from them? All the knowledge we have in agriculture, gardening, chemistry, and medicine, is built upon the same foundation. And if ever our philosophy concerning the human mind is carried so far as to deserve the name of science, which ought never to be despaired of, it must be by observing facts, reducing them to general rules, and drawing just conclusions from them. What we commonly call natural causes might, with more propriety, be called natural signs, and what we call effects, the things signified. The causes have no proper efficiency or causality, as far as we know; and all we can certainly affirm is, that nature hath established a constant conjunction between them and the things called their effects; and hath given to mankind a disposition to observe those connections, to confide in their continuance, and to make use of them for the improvement of our knowledge, and increase of our power.

A second class is that wherein the connection between the sign and thing signified, is not only Edition: current; Page: [77] established by nature, but discovered to us by a natural principle, without reasoning or experience. Of this kind are the natural signs of human thoughts, purposes, and desires, which have been already mentioned as the natural language of mankind. An infant may be put into a fright by an angry countenance, and soothed again by smiles and blandishments. A child that has a good musical ear, may be put to sleep or to dance, may be made merry or sorrowful, by the modulation of musical sounds. The principles of all the fine arts, and of what we call a fine taste, may be resolved into connections of this kind. A fine taste may be improved by reasoning and experience; but if the first principles of it were not planted in our minds by nature, it could never be acquired. Nay, we have already made it appear, that a great part of this knowledge which we have by nature, is lost by the disuse of natural signs, and the substitution of artificial in their place.

A third class of natural signs comprehends those which, though we never before had any notion or conception of the thing signified, do suggest it, or conjure it up, as it were, by a natural kind of magic, and at once give us a conception and create a belief of it. I shewed formerly, that our sensations suggest to us a sentient being or mind to which they belong—a being which hath a permanent existence, although the sensations are Edition: current; Page: [78] transient and of short duration—a being which is still the same, while its sensations and other operations are varied ten thousand ways—a being which hath the same relation to all that infinite variety of thoughts, purposes, actions, affections, enjoyments, and sufferings, which we are conscious of, or can remember. The conception of a mind is neither an idea of sensation nor of reflection; for it is neither like any of our sensations, nor like anything we are conscious of. The first conception of it, as well as the belief of it, and of the common relation it bears to all that we are conscious of, or remember, is suggested to every thinking being, we do not know how.

The notion of hardness in bodies, as well as the belief of it, are got in a similar manner; being, by an original principle of our nature, annexed to that sensation which we have when we feel a hard body. And so naturally and necessarily does the sensation convey the notion and belief of hardness, that hitherto they have been confounded by the most acute inquirers into the principles of human nature, although they appear, upon accurate reflection, not only to be different things, but as unlike as pain is to the point of a sword.

It may be observed, that, as the first class of natural signs I have mentioned is the foundation of true philosophy, and the second the foundation Edition: current; Page: [79] of the fine arts, or of taste—so the last is the foundation of common sense—a part of human nature which hath never been explained.

I take it for granted, that the notion of hardness, and the belief of it, is first got by means of that particular sensation which, as far back as we can remember, does invariably suggest it; and that, if we had never had such a feeling, we should never have had any notion of hardness. I think it is evident, that we cannot, by reasoning from our sensations, collect the existence of bodies at all, far less any of their qualities. This hath been proved by unanswerable arguments by the Bishop of Cloyne, and by the author of the Treatise of Human Nature. It appears as evident that this connection between our sensations and the conception and belief of external existences cannot be produced by habit, experience, education, or any principle of human nature that hath been admitted by philosophers. At the same time, it is a fact that such sensations are invariably connected with the conception and belief of external existences. Hence, by all rules of just reasoning, we must conclude, that this connection is the effect of our constitution, and ought to be considered as an original principle of human nature, till we find some more general principle into which it may be resolved.1

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§ 3.: Of Extension

It is further to be observed, that hardness and softness, roughness and smoothness, figure and motion, do all suppose extension, and cannot be conceived without it; yet, I think it must, on the other hand, be allowed that, if we had never felt any thing hard or soft, rough or smooth, figured or moved, we should never have had a conception of extension; so that, as there is good ground to believe that the notion of extension could not be prior to that of other primary qualities, so it is certain that it could not be posterior to the notion of any of them, being necessarily implied in them all.

Extension, therefore, seems to be a quality suggested to us, by the very same sensations which suggest the other qualities above mentioned. When I grasp a ball in my hand, I perceive it at once hard, figured, and extended. The feeling is very simple, and hath not the least resemblance to any quality of body. Yet it suggests to us three primary qualities perfectly distinct from one another, as well as from the sensation which indicates them. When I move my hand along the table, the feeling is so simple that I find it difficult to distinguish it into things of different natures; yet, it immediately suggests hardness, smoothness, extension, and motion—things of very different natures, and all Edition: current; Page: [81] of them as distinctly understood as the feeling which suggests them.

We are commonly told by philosophers, that we get the idea of extension by feeling along the extremities of a body, as if there was no manner of difficulty in the matter. I have sought, with great pains, I confess, to find out how this idea can be got by feeling; but I have sought in vain. Yet it is one of the clearest and most distinct notions we have; nor is there anything whatsoever about which the human understanding can carry on so many long and demonstrative trains of reasoning.

The notion of extension is so familiar to us from infancy, and so constantly obtruded by everything we see and feel, that we are apt to think it obvious how it comes into the mind; but upon a narrower examination we shall find it utterly inexplicable. It is true we have feelings of touch, which every moment present extension to the mind; but how they come to do so, is the question; for those feelings do no more resemble extension than they resemble justice or courage—nor can the existence of extended things be inferred from those feelings by any rules of reasoning; so that the feelings we have by touch, can neither explain how we get the notion, nor how we come by the belief of extended things.

What hath imposed upon philosophers in this matter is, that the feelings of touch, which suggest Edition: current; Page: [82] primary qualities, have no names, nor are they ever reflected upon. They pass through the mind instantaneously, and serve only to introduce the notion and belief of external things, which, by our constitution, are connected with them. They are natural signs, and the mind immediately passes to the thing signified, without making the least reflection upon the sign, or observing that there was any such thing. Hence it hath always been taken for granted, that the ideas of extension, figure, and motion, are ideas of sensation, which enter into the mind by the sense of touch, in the same manner as the sensation of sound and smell do by the ear and nose. The sensations of touch are so connected, by our constitution, with the notions of extension, figure, and motion, that philosophers have mistaken the one for the other, and never have been able to discern that they were not only distinct things, but altogether unlike. However, if we will reason distinctly upon this subject, we ought to give names to those feelings of touch; we must accustom ourselves to attend to them, and to reflect upon them, that we may be able to disjoin them from, and to compare them with, the qualities signified or suggested by them.

The habit of doing this is not to be attained without pains and practice; and till a man hath acquired this habit, it will be impossible for him to think distinctly, or to judge right, upon this subject.

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Let a man press his hand against the table—he feels it hard. But what is the meaning of this?—The meaning undoubtedly is, that he hath a certain feeling of touch, from which he concludes, without any reasoning, or comparing ideas, that there is something external really existing, whose parts stick so firmly together, that they cannot be displaced without considerable force.

There is here a feeling, and a conclusion drawn from it, or some way suggested by it. In order to compare these, we must view them separately, and then consider by what tie they are connected, and wherein they resemble one another. The hardness of the table is the conclusion, the feeling is the medium by which we are led to that conclusion. Let a man attend distinctly to this medium, and to the conclusion, and he will perceive them to be as unlike as any two things in nature. The one is a sensation of the mind, which can have no existence but in a sentient being; nor can it exist one moment longer than it is felt; the other is in the table, and we conclude, without any difficulty, that it was in the table before it was felt, and continues after the feeling is over. The one implies no kind of extension, nor parts, nor cohesion; the other implies all these. Both, indeed, admit of degrees, and the feeling, beyond a certain degree, is a species of pain; but adamantine hardness does not imply the least pain.

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And as the feeling hath no similitude to hardness, so neither can our reason perceive the least tie or connection between them; nor will the logician ever be able to shew a reason why we should conclude hardness from this feeling, rather than softness, or any other quality whatsoever. But, in reality, all mankind are led by their constitution to conclude hardness from this feeling.

The sensation of heat, and the sensation we have by pressing a hard body, are equally feelings; nor can we, by reasoning, draw any conclusion from the one but what may be drawn from the other: but, by our constitution, we conclude from the first an obscure or occult quality, of which we have only this relative conception, that it is something adapted to raise in us the sensation of heat; from the second, we conclude a quality of which we have a clear and distinct conception—to wit, the hardness of the body.1

§ 4.: Of the Visible Appearances of Objects

In this section we must speak of things which are never made the object of reflection, though almost every moment presented to the mind. Nature intended them only for signs; and in the whole course of life they are put to no other use. The mind has acquired a confirmed and inveterate habit of inattention to them; for they no sooner appear, Edition: current; Page: [85] than quick as lightning the thing signified succeeds, and engrosses all our regard. They have no name in language; and, although we are conscious of them when they pass through the mind, yet their passage is so quick and so familiar, that it is absolutely unheeded; nor do they leave any footsteps of themselves, either in the memory or imagination. That this is the case with regard to the sensations of touch, hath been shewn in the last chapter; and it holds no less with regard to the visible appearances of objects.1

By colour, all men, who have not been tutored by modern philosophy, understand, not a sensation of the mind, which can have no existence when it is not perceived, but a quality or modification of bodies, which continues to be the same whether it is seen or not. The scarlet-rose which is before me, is still a scarlet-rose when I shut my eyes, and was so at midnight when no eye saw it. The colour remains when the appearance ceases; it remains the same when the appearance changes. For when I view this scarlet-rose through a pair of green spectacles, the appearance is changed; but I do not conceive the colour of the rose changed. To a person in the jaundice, it has still another appearance; but he is easily convinced that the change is in his eye, and not in the colour of the object. Every different degree of light makes it have a Edition: current; Page: [86] different appearance, and total darkness takes away all appearance, but makes not the least change in the colour of the body. We may, by a variety of optical experiments, change the appearance of figure and magnitude in a body, as well as that of colour; we may make one body appear to be ten. But all men believe, that, as a multiplying glass does not really produce ten guineas out of one, nor a microscope turn a guinea into a ten-pound piece, so neither does a coloured glass change the real colour of the object seen through it, when it changes the appearance of that colour.

The common language of mankind shews evidently, that we ought to distinguish between the colour of a body, which is conceived to be a fixed and permanent quality in the body, and the appearance of that colour to the eye, which may be varied a thousand ways, by a variation of the light, of the medium, or of the eye itself. The permanent colour of the body is the cause which, by the mediation of various kinds or degrees of light, and of various transparent bodies interposed, produces all this variety of appearances. When a coloured body is presented, there is a certain apparition to the eye, or to the mind, which we have called the appearance of colour. Mr Locke calls it an idea; and, indeed, it may be called so with the greatest propriety. This idea can have no existence but when it is perceived. It is a kind Edition: current; Page: [87] of thought, and can only be the act of a percipient or thinking being. By the constitution of our nature, we were led to conceive this idea as a sign of something external, and are impatient till we learn its meaning. A thousand experiments for this purpose are made every day by children, even before they come to the use of reason. They look at things, they handle them, they put them in various positions, at different distances, and in different lights. The ideas of sight, by these means, come to be associated with, and readily to suggest, things external, and altogether unlike them. In particular, that idea which we have called the appearance of colour, suggests the conception and belief of some unknown quality in the body which occasions the idea; and it is to this quality, and not to the idea, that we give the name of colour.1

Although there is no resemblance, nor, as far as we know, any necessary connection between that quality in a body which we call its colour, and the appearance which that colour makes to the eye, it is quite otherwise with regard to its figure and magnitude. There is certainly a resemblance, and a necessary connection, between the visible figure and magnitude of a body, and its real figure and magnitude; no man can give a reason why a scarlet colour affects the eye in the manner it does; Edition: current; Page: [88] no man can be sure that it affects his eye in the same manner as it affects the eye of another, and that it has the same appearance to him as it has to another man;—but we can assign a reason why a circle placed obliquely to the eye, should appear in the form of an ellipse. The visible figure, magnitude, and position may, by mathematical reasoning, be deduced from the real; and it may be demonstrated, that every eye that sees distinctly and perfectly, must, in the same situation, see it under this form, and no other. Nay, we may venture to affirm, that a man born blind, if he were instructed in mathematics, would be able to determine the visible figure of a body, when its real figure, distance, and position, are given.1

Since the visible figure of bodies is a real and external object to the eye, as their tangible figure is to the touch, it may be asked, Whence arises the difficulty of attending to the first, and the facility of attending to the last? It is certain that the first is more frequently presented to the eye, than the last is to the touch; the first is as distinct and determinate an object as the last, and seems in its own nature as proper for speculation. Yet so little hath it been attended to, that it never had a name in any language, until Bishop Berkeley gave it that which we have used after his example, to distinguish it from the figure which is the object of touch.

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The difficulty of attending to the visible figure of bodies, and making it an object of thought, appears so similar to that which we find in attending to our sensations, that both have probably like causes. Nature intended the visible figure as a sign of the tangible figure and situation of bodies, and hath taught us, by a kind of instinct, to put it always to this use. Hence it happens, that the mind passes over it with a rapid motion, to attend to the things signified by it. It is as unnatural to the mind to stop at the visible figure, and attend to it, as it is to a spherical body to stop upon an inclined plane. There is an inward principle, which constantly carries it forward, and which cannot be overcome but by a contrary force.1

§ 5.: Of Perception in General

Sensation, and the perception of external objects by the senses, though very different in their nature, have commonly been considered as one and the same thing. The purposes of common life do not make it necessary to distinguish them, and the received opinions of philosophers tend rather to confound them; but, without attending carefully to this distinction, it is impossible to have any just conception of the operations of our senses. The most simple operations of the mind, admit not of a logical definition: all we can do is to describe Edition: current; Page: [90] them, so as to lead those who are conscious of them in themselves, to attend to them, and reflect upon them; and it is often very difficult to describe them so as to answer this intention.

The same mode of expression is used to denote sensation and perception; and, therefore, we are apt to look upon them as things of the same nature. Thus, I feel a pain; I see a tree: the first denoteth a sensation, the last a perception. The grammatical analysis of both expressions is the same: for both consist of an active verb and an object. But, if we attend to the things signified by these expressions, we shall find that, in the first, the distinction between the act and the object is not real but grammatical; in the second, the distinction is not only grammatical but real.

The form of the expression, I feel pain, might seem to imply that the feeling is something distinct from the pain felt; yet, in reality, there is no distinction. As thinking a thought is an expression which could signify no more than thinking, so feeling a pain signifies no more than being pained. What we have said of pain is applicable to every other mere sensation. It is difficult to give instances, very few of our sensations having names; and, where they have, the name being common to the sensation, and to something else which is associated with it. But, when we attend to the sensation by itself, and separate it from other Edition: current; Page: [91] things which are conjoined with it in the imagination, it appears to be something which can have no existence but in a sentient mind, no distinction from the act of the mind by which it is felt.

Perception, as we here understand it, hath always an object distinct from the act by which it is perceived; an object which may exist whether it be perceived or not. I perceive a tree that grows before my window; there is here an object which is perceived, and an act of the mind by which it is perceived; and these two are not only distinguishable, but they are extremely unlike in their natures. The object is made up of a trunk, branches, and leaves; but the act of the mind by which it is perceived hath neither trunk, branches, nor leaves. I am conscious of this act of my mind, and I can reflect upon it; but it is too simple to admit of an analysis, and I cannot find proper words to describe it. I find nothing that resembles it so much as the remembrance of the tree, or the imagination of it. Yet both these differ essentially from perception; they differ likewise one from another. It is in vain that a philosopher assures me, that the imagination of the tree, the remembrance of it, and the perception of it, are all one, and differ only in degree of vivacity. I know the contrary; for I am as well acquainted with all the three as I am with the apartments of my own house. I know this also, that the perception of an object implies Edition: current; Page: [92] both a conception of its form, and a belief of its present existence. I know, moreover, that this belief is not the effect of argumentation and reasoning; it is the immediate effect of my constitution.

I am aware that this belief which I have in perception stands exposed to the strongest batteries of scepticism. But they make no great impression upon it. The sceptic asks me, Why do you believe the existence of the external object which you perceive? This belief, sir, is none of my manufacture; it came from the mint of Nature; it bears her image and superscription; and, if it is not right, the fault is not mine: I even took it upon trust, and without suspicion. Reason, says the sceptic, is the only judge of truth, and you ought to throw off every opinion and every belief that is not grounded on reason. Why, sir, should I believe the faculty of reason more than that of perception?—they came both out of the same shop, and were made by the same artist; and if he puts one piece of false ware into my hands, what should hinder him from putting another?1

Our perceptions are of two kinds: some are natural and original; others acquired, and the fruit of experience. When I perceive that this is the taste of cyder, that of brandy; that this is the smell of an apple, that of an orange; that this is the noise of thunder, that the ringing of bells; this Edition: current; Page: [93] the sound of a coach passing, that the voice of such a friend: these perceptions, and others of the same kind, are not original—they are acquired. But the perception which I have, by touch, of the hardness and softness of bodies, of their extension, figure, and motion, is not acquired—it is original.

In all our senses, the acquired perceptions are many more than the original, especially in sight. By this sense we perceive originally the visible figure and colour of bodies only, and their visible place: but we learn to perceive by the eye almost everything which we can perceive by touch. The original perceptions of this sense serve only as signs to introduce the acquired.

The signs by which objects are presented to us in perception, are the language of Nature to man; and as, in many respects, it hath great affinity with the language of man to man, so particularly in this, that both are partly natural and original, partly acquired by custom. Our original or natural perceptions are analogous to the natural language of man to man, of which we took notice in the fourth chapter; and our acquired perceptions are analogous to artificial language, which, in our mother-tongue, is got very much in the same manner with our acquired perceptions—as we shall afterwards more fully explain.

Not only men, but children, idiots, and brutes, acquire by habit many perceptions which they had Edition: current; Page: [94] not originally. Almost every employment in life hath perceptions of this kind that are peculiar to it. The shepherd knows every sheep of his flock, as we do our acquaintance, and can pick them out of another flock one by one. The butcher knows by sight the weight and quality of his beeves and sheep before they are killed. The farmer perceives by his eye, very nearly, the quantity of hay in a rick, or of corn in a heap. The sailor sees the burthen, the build, and the distance of a ship at sea, while she is a great way off. Every man accustomed to writing, distinguishes his acquaintance by their handwriting, as he does by their faces. And the painter distinguishes, in the works of his art, the style of all the great masters. In a word, acquired perception is very different in different persons, according to the diversity of objects about which they are employed, and the application they bestow in observing them.

Perception ought not only to be distinguished from sensation, but likewise from that knowledge of the objects of sense which is got by reasoning. There is no reasoning in perception, as hath been observed. The belief which is implied in it, is the effect of instinct. But there are many things, with regard to sensible objects, which we can infer from what we perceive; and such conclusions of reason ought to be distinguished from what is merely perceived. When I look at the moon, I perceive Edition: current; Page: [95] her to be sometimes circular, sometimes horned, and sometimes gibbous. This is simple perception, and is the same in the philosopher and in the clown: but from these various appearances of her enlightened part, I infer that she is really of a spherical figure. This conclusion is not obtained by simple perception, but by reasoning. Simple perception has the same relation to the conclusions of reason drawn from our perceptions, as the axioms in mathematics have to the propositions. I cannot demonstrate that two quantities which are equal to the same quantity, are equal to each other; neither can I demonstrate that the tree which I perceive, exists. But, by the constitution of my nature, my belief is irresistibly carried along by my apprehension of the axiom; and, by the constitution of my nature, my belief is no less irresistibly carried along by my perception of the tree. All reasoning is from principles. The first principles of mathematical reasoning are mathematical axioms and definitions; and the first principles of all our reasoning about existences, are our perceptions. The first principles of every kind of reasoning are given us by Nature, and are of equal authority with the faculty of reason itself, which is also the gift of Nature. The conclusions of reason are all built upon first principles, and can have no other foundation. Most justly, therefore, do such principles disdain to be tried by reason, and Edition: current; Page: [96] laugh at all the artillery of the logician, when it is directed against them.

When a long train of reasoning is necessary in demonstrating a mathematical proposition, it is easily distinguished from an axiom; and they seem to be things of a very different nature. But there are some propositions which lie so near to axioms that it is difficult to say whether they ought to be held as axioms, or demonstrated as propositions. The same thing holds with regard to perception, and the conclusions drawn from it. Some of these conclusions follow our perceptions so easily, and are so immediately connected with them, that it is difficult to fix the limit which divides the one from the other.

Perception, whether original or acquired, implies no exercise of reason; and is common to men, children, idiots, and brutes. The more obvious conclusions drawn from our perceptions, by reason, make what we call common understanding; by which men conduct themselves in the common affairs of life, and by which they are distinguished from idiots. The more remote conclusions which are drawn from our perceptions, by reason, make what we commonly call science in the various parts of nature, whether in agriculture, medicine, mechanics, or in any part of natural philosophy. When I see a garden in good order, containing a great variety of things of the best kinds, and in Edition: current; Page: [97] the most flourishing condition, I immediately conclude from these signs the skill and industry of the gardener. A farmer, when he rises in the morning, and perceives that the neighbouring brook overflows his field, concludes that a great deal of rain hath fallen in the night. Perceiving his fence broken, and his corn trodden down, he concludes that some of his own or his neighbours’ cattle have broke loose. Perceiving that his stable door is broke open, and some of his horses gone, he concludes that a thief has carried them off. He traces the prints of his horses’ feet in the soft ground, and by them discovers which road the thief hath taken. These are instances of common understanding, which dwells so near to perception that it is difficult to trace the line which divides the one from the other. In like manner, the science of nature dwells so near to common understanding that we cannot discern where the latter ends and the former begins. I perceive that bodies lighter than water swim in water, and that those which are heavier sink. Hence I conclude, that, if a body remains wherever it is put under water, whether at the top or bottom, it is precisely of the same weight with water. If it will rest only when part of it is above water, it is lighter than water. And the greater the part above water is, compared with the whole, the lighter is the body. If it had no gravity at all, it would make no impression upon the water, Edition: current; Page: [98] but stand wholly above it. Thus, every man, by common understanding, has a rule by which he judges of the specific gravity of bodies which swim in water: and a step or two more leads him into the science of hydrostatics.

All that we know of nature, or of existences, may be compared to a tree, which hath its root, trunk, and branches. In this tree of knowledge, perception is the root, common understanding is the trunk, and the sciences are the branches.

§ 6.: Of the Process of Nature in Perception

Although there is no reasoning in perception, yet there are certain means and instruments, which, by the appointment of nature, must intervene between the object and our perception of it; and, by these, our perceptions are limited and regulated. First, If the object is not in contact with the organ of sense, there must be some medium which passes between them. Thus, in vision, the rays of light; in hearing, the vibrations of elastic air; in smelling, the effluvia of the body smelled—must pass from the object to the organ; otherwise we have no perception. Secondly, There must be some action or impression upon the organ of sense, either by the immediate application of the object, or by the medium that goes between them. Thirdly, The nerves which go from the brain to the organ must receive some impression by means Edition: current; Page: [99] of that which was made upon the organ; and, probably, by means of the nerves, some impression must be made upon the brain. Fourthly, The impression made upon the organ, nerves, and brain, is followed by a sensation. And, last of all, This sensation is followed by the perception of the object.

Thus, our perception of objects is the result of a train of operations; some of which affect the body only, others affect the mind. We know very little of the nature of some of these operations; we know not at all how they are connected together, or in what way they contribute to that perception which is the result of the whole; but, by the laws of our constitution, we perceive objects in this, and in no other way.1

Experience teaches us, that certain impressions upon the body are constantly followed by certain sensations of the mind; and that, on the other hand, certain determinations of the mind are constantly followed by certain motions of the body; but we see not the chain that ties these things together. Who knows but their connection may be arbitrary, and owing to the will of our Maker? Perhaps the same sensations might have been connected with other impressions, or other bodily organs. Perhaps we might have been so made as to taste with our fingers, to smell with our ears, and to hear by the nose. Perhaps we might have Edition: current; Page: [100] been so made as to have all the sensations and perceptions which we have, without any impression made upon our bodily organs at all.

However these things may be, if Nature had given us nothing more than impressions made upon the body, and sensations in our minds corresponding to them, we should, in that case, have been merely sentient, but not percipient beings. We should never have been able to form a conception of any external object, far less a belief of its existence. Our sensations have no resemblance to external objects; nor can we discover, by our reason, any necessary connection between the existence of the former, and that of the latter.1

Appendix: Of Cause and Power

It is proper here to explain what is meant by the cause of a phenomenon, when that word is used in natural philosophy. The word cause is so ambiguous, that I fear many mistake its meaning, and take it to mean the efficient cause, which I think it never does in this science.

By the cause of a phenomenon, nothing is meant but the law of nature, of which that phenomenon is an instance, or a necessary consequence. The cause of a body’s falling to the ground is its gravity. But gravity is not an efficient cause, but a general law, that obtains in nature, of which law the fall Edition: current; Page: [101] of this body is a particular instance. The cause why a body projected moves in a parabola, is, that this motion is the necessary consequence of the projectile force and gravity united. But these are not efficient causes; they are only laws of nature. In natural philosophy, therefore, we seek only the general laws, according to which nature works, and these we call the causes of what is done according to them. But such laws cannot be the efficient cause of anything. They are only the rule according to which the efficient cause operates.

A natural philosopher may search after the cause of a law of nature; but this means no more than searching for a more general law, which includes that particular law, and perhaps many others under it. This was all that Newton aimed at by his ether. He thought it possible, that, if there was such an ether, the gravitation of bodies, the reflection and refraction of the rays of light, and many other laws of nature, might be the necessary consequences of the elasticity and repelling force of the ether. But, supposing this ether to exist, its elasticity and repelling force must be considered as a law of nature; and the efficient cause of this elasticity would still have been latent.

Efficient causes, properly so called, are not within the sphere of natural philosophy. Its business is, from particular facts in the material world, to collect, by just induction, the laws that Edition: current; Page: [102] are general, and from these the more general, as far as we can go. And when this is done, natural philosophy has no more to do. It exhibits to our view the grand machine of the material world, analysed, as it were, and taken to pieces, with the connections and dependencies of its several parts, and the laws of its several movements. It belongs to another branch of philosophy to consider whether this machine is the work of chance or of design, and whether of good or of bad design; whether there is not an intelligent first Mover who contrived the whole, and gives motion to the whole, according to the laws which the natural philosopher has discovered, or, perhaps, according to laws still more general, of which we can only discover some branches; and whether he does these things by his own hand, so to speak, or employs subordinate efficient causes to execute his purposes. These are very noble and important inquiries, but they do not belong to natural philosophy; nor can we proceed in them in the way of experiment and induction, the only instruments the natural philosopher uses in his researches.

Whether you call this branch of philosophy Natural Theology or Metaphysics, I care not; but I think it ought not to be confounded with Natural Philosophy; and neither of them with Mathematics. Let the mathematician demonstrate the relation of abstract quantity; the natural philosopher Edition: current; Page: [103] investigate the laws of the material system by induction; and the metaphysician, the final causes, and the efficient causes of what we see and what natural philosophy discovers in the world we live in.

As to final causes, they stare us in the face wherever we cast our eyes. I can no more doubt whether the eye was made for the purpose of seeing, and the ear of hearing, than I can doubt of a mathematical axiom; yet the evidence is neither mathematical demonstration, nor is it induction. In a word, final causes, good final causes, are seen plainly everywhere: in the heavens and in the earth; in the constitution of every animal, and in our own constitution of body and of mind; and they are most worthy of observation, and have a charm in them that delights the soul.

As to efficient causes, I am afraid our faculties carry us but a very little way, and almost only to general conclusions. I hold it to be self-evident, that every production, and every change in nature, must have an efficient cause that has power to produce the effect; and that an effect which has the most manifest marks of intelligence, wisdom, and goodness, must have an intelligent, wise, and good efficient cause. From these, and some such self-evident truths, we may discover the principles of natural theology, and that the Deity is the first efficient cause of all nature. But how far he Edition: current; Page: [104] operates in nature immediately, or how far by the ministry of subordinate efficient causes, to which he has given power adequate to the task committed to them, I am afraid our reason is not able to discover, and we can do little else than conjecture. We are led by nature to believe ourselves to be the efficient causes of our own voluntary actions; and, from analogy, we judge the same of other intelligent beings. But with regard to the works of nature, I cannot recollect a single instance wherein I can say, with any degree of assurance, that such a thing is the efficient cause of such a phenomenon of nature.

I never could see good reason to believe that matter has any active power at all. And, indeed, if it were evident that it has one, I think there could be no good reason assigned for not allowing it others. Your Lordship speaks of the power of resisting motion, and some others, as acknowledged active powers inherent in matter. As to the resistance to motion, and the continuance in motion, I never could satisfy myself whether these are not the necessary consequences of matter being inactive. If they imply activity, they may lie in some other cause.

I am not able to form any distinct conception of active power but such as I find in myself. I can only exert my active power by will, which supposes thought. It seems to me, that, if I was not conscious Edition: current; Page: [105] of activity in myself, I could never, from things I see about me, have had the conception or idea of active power. I see a succession of changes, but I see not the power, that is, the efficient cause of them; but, having got the notion of active power, from the consciousness of my own activity, and finding it a first principle, that every production requires active power, I can reason about an active power of that kind I am acquainted with—that is, such as supposes thought and choice, and is exerted by will. But, if there is anything in an unthinking inanimate being that can be called active power, I know not what it is, and cannot reason about it.

If you conceive that the activity of matter is directed by thought and will in matter, every particle of matter must know the situation and distance of every other particle within the planetary system; but this, I am apt to think, is not your Lordship’s opinion.

I must therefore conclude, that this active power is guided in all its operations by some intelligent Being, who knows both the law of gravitation, and the distance and situation of every particle of matter with regard to every other particle, in all the changes that happen in the material world. I can only conceive two ways in which this particle of matter can be guided, in all the exertions of its active power, by an intelligent Being. Either it Edition: current; Page: [106] was formed, in its creation, upon a foreknowledge of all the situations it shall ever be in with respect to other particles, and had such an internal structure given it, as necessarily produces, in succession, all the motions, and tendencies to motion, it shall ever exert. This would make every particle of matter a machine or automaton, and every particle of a different structure from every other particle in the universe. This is indeed the opinion of Leibnitz; but I am not prejudiced against it upon that account; I only wished to know whether your Lordship adopted it or not. Another way, and the only other way, in which I can conceive the active power of a particle of matter, guided by an intelligent Being, is by a continual influence exerted according to its situation and the situation of other particles. In this case, the particle would be guided as a horse is by his rider; and I think it would be improper to ascribe to it the power of gravitation. It has only the power of obeying its guide. Whether your Lordship chooses the first or the last in this alternative, I should be glad to know; or whether you can think of a third way better than either.1

The ambiguity of the words power, cause, agent, and of all the words related to these, tends to perplex this question. The weakness of human Edition: current; Page: [107] understanding, which gives us only an indirect and relative conception of power, contributes to darken our reasoning, and should make us cautious and modest in our determinations.

We can derive little light in this matter from the events which we observe in the course of nature. We perceive changes innumerable in things without us. We know that those changes must be produced by the active power of some agent; but we neither perceive the agent nor the power, but the change only. Whether the things be active, or merely passive, is not easily discovered. And though it may be an object of curiosity to the speculative few, it does not greatly concern the many.

From the course of events in the natural world, we have sufficient reason to conclude the existence of an eternal intelligent First Cause. But whether He acts immediately in the production of those events, or by subordinate intelligent agents, or by instruments that are unintelligent, and what the number, the nature, and the different offices, of those agents or instruments may be—these I apprehend to be mysteries placed beyond the limits of human knowledge. We see an established order in the succession of natural events, but we see not the bond that connects them together.

Since we derive so little light, with regard to efficient causes and their active power, from attention Edition: current; Page: [108] to the natural world, let us next attend to the moral, I mean to human actions and conduct.

When I observe a plant growing from its seed to maturity, I know that there must be a cause that has power to produce this effect. But I see neither the cause nor the manner of its operation.

But, in certain motions of my body and directions of my thought, I know not only that there must be a cause that has power to produce these effects, but that I am that cause; and I am conscious of what I do in order to the production of them.

From the consciousness of our own activity, seems to be derived not only the clearest, but the only conception we can form of activity, or the exertion of active power.

As I am unable to form a notion of any intellectual power different in kind from those I possess, the same holds with respect to active power. If all men had been blind, we should have had no conception of the power of seeing, nor any name for it in language. If man had not the powers of abstraction and reasoning, we could not have had any conception of these operations. In like manner, if he had not some degree of active power, and if he were not conscious of the exertion of it in his voluntary actions, it is probable he could have no conception of activity, or of active power.

A train of events following one another ever so regularly, could never lead us to the notion of a Edition: current; Page: [109] cause, if we had not, from our constitution, a conviction of the necessity of a cause to every event.

And of the manner in which a cause may exert its active power, we can have no conception, but from consciousness of the manner in which our active power is exerted.

Every man is led by nature to attribute to himself the free determinations of his own will, and to believe those events to be in his power which depend upon his will. On the other hand, it is self-evident, that nothing is in our power that is not subject to our will.

We grow from childhood to manhood, we digest our food, our blood circulates, our heart and arteries beat, we are sometimes sick and sometimes in health; all these things must be done by the power of some agent; but they are not done by our power. How do we know this? Because they are not subject to our will. This is the infallible criterion by which we distinguish what is our doing from what is not; what is in our power from what is not.

Human power, therefore, can only be exerted by will, and we are unable to conceive any active power to be exerted without will. Every man knows infallibly that what is done by his conscious will and intention, is to be imputed to him, as the agent or cause; and that whatever is done without his will and intention, cannot be imputed to him with truth.

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We judge of the actions and conduct of other men by the same rule as we judge of our own. In morals, it is self-evident that no man can be the object either of approbation or of blame for what he did not. But how shall we know whether it is his doing or not? If the action depended upon his will, and if he intended and willed it, it is his action in the judgment of all mankind. But if it was done without his knowledge, or without his will and intention, it is as certain that he did it not, and that it ought not to be imputed to him as the agent.

Now it is evident that, to constitute the relation between me and my action, my conception of the action, and will to do it, are essential. For what I never conceived nor willed, I never did.

If any man, therefore, affirms, that a being may be the efficient cause of an action, and have power to produce it, which that being can neither conceive nor will, he speaks a language which I do not understand. If he has a meaning, his notion of power and efficiency must be essentially different from mine; and, until he conveys his notion of efficiency to my understanding, I can no more assent to his opinion than if he should affirm that a being without life may feel pain.

It seems, therefore, to me most probable, that such beings only as have some degree of understanding and will, can possess active power; and Edition: current; Page: [111] that inanimate beings must be merely passive, and have no real activity. Nothing we perceive without us affords any good ground for ascribing active power to any inanimate being; and everything we can discover in our own constitution, leads us to think that active power cannot be exerted without will and intelligence.1


§ 1.: Principles taken for Granted

As there are words common to philosophers and to the vulgar, which need no explication, so there are principles common to both, which need no proof, and which do not admit of direct proof.2

1. First, then, I shall take it for granted, that I think, that I remember, that I reason, and, in general, that I really perform all those operations of mind of which I am conscious.

The operations of our minds are attended with consciousness; and this consciousness is the evidence, the only evidence, which we have or can have of their existence. If a man should take it into his head to think or to say that his consciousness may deceive him, and to require proof that it cannot, I know of no proof that can be given him; he must Edition: current; Page: [112] be left to himself, as a man that denies first principles, without which there can be no reasoning. Every man finds himself under a necessity of believing what consciousness testifies, and everything that hath this testimony is to be taken as a first principle.

2. As by consciousness we know certainly the existence of our present thoughts and passions; so we know the past by remembrance. And, when they are recent, and the remembrance of them fresh, the knowledge of them, from such distinct remembrance, is, in its certainty and evidence, next to that of consciousness.

3. But it is to be observed that we are conscious of many things to which we give little or no attention. We can hardly attend to several things at the same time; and our attention is commonly employed about that which is the object of our thought, and rarely about the thought itself. Thus, when a man is angry, his attention is turned to the injury done him, or the injurious person; and he gives very little attention to the passion of anger, although he is conscious of it. It is in our power, however, when we come to the years of understanding, to give attention to our own thoughts and passions, and the various operations of our minds. And, when we make these the objects of our attention, either while they are present or when they are recent and fresh in our memory, this act of the mind is called reflection.

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We take it for granted, therefore, that, by attentive reflection, a man may have a clear and certain knowledge of the operations of his own mind; a knowledge no less clear and certain than that which he has of an external object when it is set before his eyes.

This reflection is a kind of intuition, it gives a like conviction with regard to internal objects, or things in the mind, as the faculty of seeing gives with regard to objects of sight. A man must, therefore, be convinced beyond possibility of doubt, of everything with regard to the operations of his own mind, which he clearly and distinctly discerns by attentive reflection.

4. I take it for granted that all the thoughts I am conscious of, or remember, are the thoughts of one and the same thinking principle, which I call myself, or my mind. Every man has an immediate and irresistible conviction, not only of his present existence, but of his continued existence and identity, as far back as he can remember. If any man should think fit to demand a proof that the thoughts he is successively conscious of, belong to one and the same thinking principle—if he should demand a proof that he is the same person to-day as he was yesterday, or a year ago—I know no proof that can be given him: he must be left to himself, either as a man that is lunatic, or as one who denies first principles, and is not to be reasoned with.

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Every man of a sound mind, finds himself under a necessity of believing his own identity, and continued existence. The conviction of this is immediate and irresistible; and, if he should lose this conviction, it would be a certain proof of insanity, which is not to be remedied by reasoning.

5. I take it for granted, that there are some things which cannot exist by themselves, but must be in something else to which they belong, as qualities, or attributes.

Thus, motion cannot exist, but in something that is moved. And to suppose that there can be motion while everything is at rest, is a gross and palpable absurdity. In like manner, hardness and softness, sweetness and bitterness, are things which cannot exist by themselves; they are qualities of something which is hard or soft, sweet or bitter. That thing, whatever it be, of which they are qualities, is called their subject; and such qualities necessarily suppose a subject.

Things which may exist by themselves, and do not necessarily suppose the existence of anything else, are called substances; and, with relation to the qualities or attributes that belong to them, they are called the subjects of such qualities or attributes.

All the things which we immediately perceive by our senses, and all the things we are conscious of, are things which must be in something else, as Edition: current; Page: [115] their subject. Thus, by my senses, I perceive figure, colour, hardness, softness, motion, resistance, and such like things. But these are qualities, and must necessarily be in something that is figured, coloured, hard or soft, that moves, or resists. It is not to these qualities, but to that which is the subject of them, that we give the name of body. If any man should think fit to deny that these things are qualities, or that they require any subject, I leave him to enjoy his opinion as a man who denies first principles, and is not fit to be reasoned with. If he has common understanding, he will find that he cannot converse half an hour without saying things which imply the contrary of what he professes to believe.

In like manner, the things I am conscious of, such as thought, reasoning, desire, necessarily suppose something that thinks, that reasons, that desires. We do not give the name of mind to thought, reason, or desire; but to that being which thinks, which reasons, and which desires.

That every act or operation, therefore, supposes an agent, that every quality supposes a subject, are things which I do not attempt to prove, but take for granted.1

6. I take it for granted, that, in most operations of the mind, there must be an object distinct from the operation itself. I cannot see, without seeing Edition: current; Page: [116] something. To see without having any object of sight is absurd. I cannot remember, without remembering something. The thing remembered is past, while the remembrance of it is present; and, therefore, the operation and the object of it must be distinct things.

7. We ought likewise to take for granted, as first principles, things wherein we find an universal agreement, among the learned and unlearned, in the different nations and ages of the world.

8. I need hardly say that I shall also take for granted such facts as are attested to the conviction of all sober and reasonable men, either by our senses, by memory, or by human testimony.1

Upon the whole, I acknowledge that we ought to be cautious that we do not adopt opinions as first principles which are not entitled to that character. But there is surely the least danger of men’s being imposed upon in this way, when such principles openly lay claim to the character, and are thereby fairly exposed to the examination of those who may dispute their authority. We do not pretend that those things that are laid down as first principles may not be examined, and that we ought not to have our ears open to what may be pleaded against their being admitted as such. Let us deal with them as an upright judge does with a witness who has a fair character. He pays Edition: current; Page: [117] a regard to the testimony of such a witness while his character is unimpeached; but, if it can be shown that he is suborned, or that he is influenced by malice or partial favour, his testimony loses all its credit, and is justly rejected.1

§ 2.: Of Hypotheses and Analogy

Let us lay down this as a fundamental principle in our inquiries into the structure of the mind and its operation—that no regard is due to the conjectures or hypotheses of philosophers, however ancient, however generally received. Let us accustom ourselves to try every opinion by the touchstone of fact and experience. What can fairly be deduced from facts duly observed or sufficiently attested, is genuine and pure; it is the voice of God, and no fiction of human imagination.

If a philosopher, therefore, pretends to shew us the cause of any natural effect, whether relating to matter or to mind, let us first consider whether there is sufficient evidence that the cause he assigns does really exist. If there is not, reject it with disdain, as a fiction which ought to have no place in genuine philosophy. If the cause assigned really exists, consider, in the next place, whether the effect it is brought to explain necessarily follows from it. Unless it has these two conditions, it is good for nothing.2

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The conclusion I would draw from all that has been said on analogy, is, that, in our inquiries concerning the mind and its operations, we ought never to trust to reasonings drawn from some supposed similitude of body to mind; and that we ought to be very much upon our guard that we be not imposed upon by those analogical terms and phrases, by which the operations of the mind are expressed in all languages.1

§ 3.: Of Perception

If we attend to that act of our mind which we call the perception of an external object of sense, we shall find in it these three things:—First, Some conception or notion of the object perceived; Secondly, A strong and irresistible conviction and belief of its present existence; and, Thirdly, That this conviction and belief are immediate, and not the effect of reasoning.

First, It is impossible to perceive an object without having some notion or conception of that which we perceive. We may, indeed, conceive an object which we do not perceive; but, when we perceive the object, we must have some perception of it at the same time; and we have commonly a more clear and steady notion of the object while we perceive it, than we have from memory or imagination when it is not perceived. Yet, even in perception, Edition: current; Page: [119] the notion which our senses give of the object may be more or less clear, more or less distinct, in all possible degrees.

Thus we see more distinctly an object at a small than at a great distance. An object at a great distance is seen more distinctly in a clear than in a foggy day. An object seen indistinctly with the naked eye, on account of its smallness, may be seen distinctly with a microscope. The objects in this room will be seen by a person in the room less and less distinctly as the light of the day fails; they pass through all the various degrees of distinctness according to the degrees of the light, and, at last, in total darkness they are not seen at all. What has been said of the objects of sight is so easily applied to the objects of the other senses, that the application may be left to the reader.

In a matter so obvious to every person capable of reflection, it is necessary only farther to observe, that the notion which we get of an object, merely by our external sense, ought not to be confounded with that more scientific notion which a man, come to the years of understanding, may have of the same object, by attending to its various attributes, or to its various parts, and their relation to each other, and to the whole. Thus, the notion which a child has of a jack for roasting meat, will be acknowledged to be very different from that of a man who Edition: current; Page: [120] understands its construction, and perceives the relation of the parts to one another, and to the whole. The child sees the jack and every part of it as well as the man. The child, therefore, has all the notion of it which sight gives; whatever there is more in the notion which the man forms of it, must be derived from other powers of the mind, which may afterwards be explained. This observation is made here only that we may not confound the operations of different powers of the mind, which by being always conjoined after we grow up to understanding, are apt to pass for one and the same.

Secondly, In perception we not only have a notion more or less distinct of the object perceived, but also an irresistible conviction and belief of its existence. This is always the case when we are certain that we perceive it. There may be a perception so faint and indistinct as to leave us in doubt whether we perceive the object or not. Thus, when a star begins to twinkle as the light of the sun withdraws, one may, for a short time, think he sees it without being certain, until the perception acquire some strength and steadiness. When a ship just begins to appear in the utmost verge of the horizon, we may at first be dubious whether we perceive it or not; but when the perception is in any degree clear and steady, there remains no doubt of its reality; and when the reality of the perception Edition: current; Page: [121] is ascertained, the existence of the object perceived can no longer be doubted.1

I observed, Thirdly, That this conviction is not only irresistible, but it is immediate; that is, it is not by a train of reasoning and argumentation that we come to be convinced of the existence of what we perceive; we ask no argument for the existence of the object, but that we perceive it; perception commands our belief upon its own authority, and disdains to rest its authority upon any reasoning whatsoever.

The conviction of a truth may be irresistible, and yet not immediate. Thus, my conviction that the three angles of every plain triangle are equal to two right angles, is irresistible, but it is not immediate; I am convinced of it by demonstrative reasoning. There are other truths in mathematics of which we have not only an irresistible but an immediate conviction. Such are the axioms. Our belief of the axioms in mathematics is not grounded upon argument—arguments are grounded upon them; but their evidence is discerned immediately by the human understanding.

It is, no doubt, one thing to have an immediate conviction of a self-evident axiom; it is another thing to have an immediate conviction of the existence of what we see; but the conviction is equally immediate and equally irresistible in both cases.2

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§ 4.: Of Sensation

Almost all our perceptions have corresponding sensations which constantly accompany them, and, on that account, are very apt to be confounded with them. Neither ought we to expect that the sensation, and its corresponding perception, should be distinguished in common language, because the purposes of common life do not require it. Language is made to serve the purposes of ordinary conversation; and we have no reason to expect that it should make distinctions that are not of common use. Hence it happens, that a quality perceived, and the sensation corresponding to that perception, often go under the same name.

This makes the names of most of our sensations ambiguous, and this ambiguity hath very much perplexed philosophers. It will be necessary to give some instances, to illustrate the distinction between our sensations and the objects of perception.

When I smell a rose, there is in this operation both sensation and perception. The agreeable odour I feel, considered by itself, without relation to any external object, is merely a sensation. It affects the mind in a certain way; and this affection of the mind may be conceived, without a thought of the rose, or any other object. This sensation can be nothing else than it is felt to be. Its very essence consists in being felt; and, when it is not Edition: current; Page: [123] felt, it is not. There is no difference between the sensation and the feeling of it—they are one and the same thing. It is for this reason that we before observed that, in sensation, there is no object distinct from that act of the mind by which it is felt—and this holds true with regard to all sensations.

Let us next attend to the perception which we have in smelling a rose. Perception has always an external object; and the object of my perception, in this case, is that quality in the rose which I discern by the sense of smell. Observing that the agreeable sensation is raised when the rose is near, and ceases when it is removed, I am led, by my nature, to conclude some quality to be in the rose, which is the cause of this sensation. This quality in the rose is the object perceived; and that act of my mind by which I have the conviction and belief of this quality, is what in this case I call perception.

But it is here to be observed, that the sensation I feel, and the quality in the rose which I perceive, are both called by the same name. The smell of a rose is the name given to both: so that this name hath two meanings; and the distinguishing its different meaning removes all perplexity, and enables us to give clear and distinct answers to questions about which philosophers have held much dispute.

Thus, if it is asked, whether the smell be in the Edition: current; Page: [124] rose, or in the mind that feels it, the answer is obvious: That there are two different things signified by the smell of a rose; one of which is in the mind, and can be in nothing but in a sentient being; the other is truly and properly in the rose. The sensation which I feel is in my mind. The mind is the sentient being; and, as the rose is insentient, there can be no sensation, nor anything resembling sensation in it. But this sensation in my mind is occasioned by a certain quality in the rose, which is called by the same name with the sensation, not on account of any similitude, but because of their constant concomitancy.

All the names we have for smells, tastes, sounds, and for the various degrees of heat and cold, have a like ambiguity; and what has been said of the smell of a rose may be applied to them. They signify both a sensation, and a quality perceived by means of that sensation. The first is the sign, the last the thing signified. As both are conjoined by nature, and as the purposes of common life do not require them to be disjoined in our thoughts, they are both expressed by the same name: and this ambiguity is to be found in all languages, because the reason of it extends to all.1

Sensation, taken by itself, implies neither the conception nor belief of any external object. It supposes a sentient being, and a certain manner in Edition: current; Page: [125] which that being is affected; but it supposes no more. Perception implies an immediate conviction and belief of something external — something different both from the mind that perceives, and from the act of perception. Things so different in their nature ought to be distinguished; but, by our constitution, they are always united. Every different perception is conjoined with a sensation that is proper to it. The one is the sign, the other the thing signified. They coalesce in our imagination. They are signified by one name, and are considered as one simple operation. The purposes of life do not require them to be distinguished.

It is the philosopher alone who has occasion to distinguish them, when he would analyse the operation compounded of them. But he has no suspicion that there is any composition in it; and to discover this requires a degree of reflection which has been too little practised even by philosophers.1

§ 5.: Of Primary and Secondary Qualities

Every one knows that extension, divisibility, figure, motion, solidity, hardness, softness, and fluidity, were by Mr Locke called primary qualities of body; and that sound, colour, taste, smell, and heat or cold, were called secondary qualities. Is there a just foundation for this distinction? Edition: current; Page: [126] Is there anything common to the primary which belongs not to the secondary? And what is it?

I answer, That there appears to me to be a real foundation for the distinction; and it is this—that our senses give us a direct and a distinct notion of the primary qualities, and inform us what they are in themselves. But of the secondary qualities, our senses give us only a relative and obscure notion. They inform us only, that they are qualities that affect us in a certain manner—that is, produce in us a certain sensation; but as to what they are in themselves, our senses leave us in the dark.

Every man capable of reflection may easily satisfy himself that he has a perfectly clear and distinct notion of extension, divisibility, figure, and motion. The solidity of a body means no more but that it excludes other bodies from occupying the same place at the same time. Hardness, softness, and fluidity are different degrees of cohesion in the parts of a body. It is fluid when it has no sensible cohesion; soft, when the cohesion is weak; and hard, when it is strong. Of the cause of this cohesion we are ignorant, but the thing itself we understand perfectly, being immediately informed of it by the sense of touch. It is evident, therefore, that of the primary qualities we have a clear and distinct notion; we know what they are, though we may be ignorant of their causes.

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I observed, farther, that the notion we have of primary qualities is direct, and not relative only. A relative notion of a thing, is, strictly speaking, no notion of the thing at all, but only of some relation which it bears to something else.

Thus, gravity sometimes signifies the tendency of bodies towards the earth; sometimes it signifies the cause of that tendency. When it means the first, I have a direct and distinct notion of gravity; I see it, and feel it, and know perfectly what it is; but this tendency must have a cause. We give the same name to the cause; and that cause has been an object of thought and of speculation. Now, what notion have we of this cause when we think and reason about it? It is evident we think of it as an unknown cause, of a known effect. This is a relative notion; and it must be obscure, because it gives us no conception of what the thing is, but of what relation it bears to something else. Every relation which a thing unknown bears to something that is known, may give a relative notion of it; and there are many objects of thought and of discourse of which our faculties can give no better than a relative notion.

Having premised these things to explain what is meant by a relative notion, it is evident that our notion of primary qualities is not of this kind; we know what they are, and not barely what relation they bear to something else.

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It is otherwise with secondary qualities. If you ask me, what is that quality or modification in a rose which I call its smell, I am at a loss to answer directly. Upon reflection, I find, that I have a distinct notion of the sensation which it produces in my mind. But there can be nothing like to this sensation in the rose, because it is insentient. The quality in the rose is something which occasions the sensation in me; but what that something is, I know not. My senses give me no information upon this point. The only notion, therefore, my senses give is this—that smell in the rose is an unknown quality or modification, which is the cause or occasion of a sensation which I know well. The relation which this unknown quality bears to the sensation with which nature hath connected it, is all I learn from the sense of smelling; but this is evidently a relative notion. The same reasoning will apply to every secondary quality.1

§ 6.: Of Conception

Without attempting a definition of this operation of the mind, I shall endeavour to explain some of its properties; consider the theories about it; and take notice of some mistakes of philosophers concerning it.

It may be observed that conception enters as an ingredient in every operation of the mind. Our Edition: current; Page: [129] senses cannot give us the belief of any object, without giving some conception of it at the same time. No man can either remember or reason about things of which he hath no conception. When we will to exert any of our active powers, there must be some conception of what we will to do. There can be no desire nor aversion, love nor hatred, without some conception of the object. We cannot feel pain without conceiving it, though we can conceive it without feeling it. These things are self-evident.

In every operation of the mind, therefore, in everything we call thought, there must be conception. When we analyse the various operations either of the understanding or of the will, we shall always find this at the bottom, like the caput mortuum of the chemists, or the materia prima of the Peripatetics; but, though there is no operation of mind without conception, yet it may be found naked, detached from all others, and then it is called simple apprehension, or the bare conception of a thing.

As all the operations of our mind are expressed by language, every one knows that it is one thing to understand what is said, to conceive or apprehend its meaning, whether it be a word, a sentence, or a discourse; it is another thing to judge of it, to assent or dissent, to be persuaded or moved. The first is simple apprehension and may be without the last; but the last cannot be without the first.

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In bare conception there can neither be truth nor falsehood, because it neither affirms nor denies. Every judgment, and every proposition by which judgment is expressed, must be true or false; and the qualities of true and false, in their proper sense, can belong to nothing but to judgments, or to propositions which express judgment. In the bare conception of a thing there is no judgment, opinion, or belief included, and therefore it cannot be either true or false.1

If one should ask, What is meant by conceiving a thing? we should very naturally answer, that it is having an image of it in the mind—and perhaps we could not explain the word better. This shews that conception, and the image of a thing in the mind, are synonymous expressions. The image in the mind, therefore, is not the object of conception, nor is it any effect produced by conception as a cause. It is conception itself. That very mode of thinking which we call conception, is by another name called an image in the mind.

Nothing more readily gives the conception of a thing than the seeing an image of it. Hence, by a figure common in language, conception is called an image of the thing conceived. But to shew that it is not a real but a metaphorical image, it is called an image in the mind. We know nothing that is properly in the mind but thought; and, when Edition: current; Page: [131] anything else is said to be in the mind, the expression must be figurative, and signify some kind of thought.1

Imagination, when it is distinguished from conception, seems to me to signify one species of conception—to wit, the conception of visible objects. Thus, in a mathematical proposition, I imagine the figure, and I conceive the demonstration; it would not, I think, be improper to say, I conceive both; but it would not be so proper to say, I imagine the demonstration.2

The last property I shall mention of this faculty, is that which essentially distinguishes it from every other power of the mind; and it is, that it is not employed solely about things which have existence. I can conceive a winged horse or a centaur, as easily and as distinctly as I can conceive a man whom I have seen. Nor does this distinct conception incline my judgment in the least to the belief that a winged horse or a centaur ever existed.

It is not so with the other operations of our minds. They are employed about real existences, and carry with them the belief of their objects. When I feel pain, I am compelled to believe that the pain that I feel has a real existence. When I perceive any external object, my belief of the real existence of the object is irresistible. When I distinctly remember any event, though that event Edition: current; Page: [132] may not now exist, I can have no doubt but it did exist. That consciousness which we have of the operations of our own minds, implies a belief of the real existence of those operations.

Thus we see, that the powers of sensation, of perception, of memory, and of consciousness, are all employed solely about objects that do exist, or have existed. But conception is often employed about objects that neither do, nor did, nor will exist. This is the very nature of this faculty, that its object, though distinctly conceived, may have no existence. Such an object we call a creature of imagination; but this creature never was created.1

§ 7.: Of Judgment

First, Judgment is an act of the mind, specifically different from simple apprehension, or the bare conception of a thing. It would be unnecessary to observe this, if some philosophers had not been led by their theories to a contrary opinion.

Although there can be no judgment without a conception of the things about which we judge, yet conception may be without any judgment. Judgment can be expressed by a proposition only, and a proposition is a complete sentence; but simple apprehension may be expressed by a word or words, which make no complete sentence. When simple apprehension is employed about a proposition, Edition: current; Page: [133] every man knows that it is one thing to apprehend a proposition—that is, to conceive what it means—but it is quite another thing to judge it to be true or false.

It is self-evident that every judgment must be either true or false; but simple apprehension, or conception, can neither be true nor false, as was shewn before.

One judgment may be contradictory to another; and it is impossible for a man to have two judgments at the same time, which he perceives to be contradictory. But contradictory propositions may be conceived at the same time without any difficulty. That the sun is greater than the earth, and that the sun is not greater than the earth, are contradictory propositions. He that apprehends the meaning of one, apprehends the meaning of both. But it is impossible for him to judge both to be true at the same time. He knows that, if the one is true, the other must be false. For these reasons, I hold it to be certain that judgment and simple apprehension are acts of the mind specifically different.

Secondly, There are notions or ideas that ought to be referred to the faculty of judgment as their source; because, if we had not that faculty, they could not enter into our minds; and to those that have that faculty, and are capable of reflecting upon its operations, they are obvious and familiar.

Among these we may reckon the notion of judgment Edition: current; Page: [134] itself; the notions of a proposition—of its subject, predicate, and copula; of affirmation and negation, of true and false; of knowledge, belief, disbelief, opinion, assent, evidence. From no source could we acquire these notions, but from reflecting upon our judgments. Relations of things make one great class of our notions or ideas; and we cannot have the idea of any relation without some exercise of judgment, as will appear afterwards.

Thirdly, In persons come to years of understanding, judgment necessarily accompanies all sensation, perception by the senses, consciousness, and memory, but not conception.

I restrict this to persons come to the years of understanding, because it may be a question, whether infants, in the first period of life, have any judgment or belief at all. The same question may be put with regard to brutes and some idiots. This question is foreign to the present subject; and I say nothing here about it, but speak only of persons who have the exercise of judgment.

In them it is evident that a man who feels pain, judges and believes that he is really pained. The man who perceives an object, believes that it exists, and is what he distinctly perceives it to be; nor is it in his power to avoid such judgment. And the like may be said of memory, and of consciousness. Whether judgment ought to be called a necessary concomitant of these operations, or rather a part Edition: current; Page: [135] or ingredient of them, I do not dispute; but it is certain that all of them are accompanied with a determination that something is true or false, and a consequent belief. If this determination be not judgment, it is an operation that has got no name; for it is not simple apprehension, neither is it reasoning; it is a mental affirmation or negation; it may be expressed by a proposition affirmative or negative, and it is accompanied with the firmest belief. These are the characteristics of judgment; and I must call it judgment, till I can find another name to it.

The judgments we form are either of things necessary, or of things contingent. That three times three is nine, that the whole is greater than a part, are judgments about things necessary. Our assent to such necessary propositions is not grounded upon any operation of sense, of memory, or of consciousness, nor does it require their concurrence; it is unaccompanied by any other operation but that of conception, which must accompany all judgment; we may therefore call this judgment of things necessary pure judgment. Our judgment of things contingent must always rest upon some other operation of the mind, such as sense, or memory, or consciousness, or credit in testimony, which is itself grounded upon sense.

That I now write upon a table covered with green cloth, is a contingent event, which I judge to be most Edition: current; Page: [136] undoubtedly true. My judgment is grounded upon my perception, and is a necessary concomitant or ingredient of my perception. That I dined with such a company yesterday, I judge to be true, because I remember it; and my judgment necessarily goes along with this remembrance, or makes a part of it.

There are many forms of speech in common language which shew that the senses, memory and consciousness, are considered as judging faculties. We say that a man judges of colours by his eye, of sounds by his ear. We speak of the evidence of sense, the evidence of memory, the evidence of consciousness. Evidence is the ground of judgment; and when we see evidence, it is impossible not to judge.

When we speak of seeing or remembering anything, we, indeed, hardly ever add that we judge it to be true. But the reason of this appears to be, that such an addition would be mere superfluity of speech, because every one knows that what I see or remember, I must judge to be true, and cannot do otherwise.

And, for the same reason, in speaking of anything that is self-evident or strictly demonstrated, we do not say that we judge it to be true. This would be superfluity of speech, because every man knows that we must judge that to be true which we hold self-evident or demonstrated.

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When you say you saw such a thing, or that you distinctly remember it, or when you say of any proposition that it is self-evident, or strictly demonstrated, it would be ridiculous after this to ask whether you judge it to be true; nor would it be less ridiculous in you to inform us that you do. It would be a superfluity of speech of the same kind as if, not content with saying that you saw such an object, you should add that you saw it with your eyes.

There is, therefore, good reason why, in speaking or writing, judgment should not be expressly mentioned, when all men know it to be necessarily implied; that is, when there can be no doubt. In such cases, we barely mention the evidence. But when the evidence mentioned leaves room for doubt, then, without any superfluity or tautology, we say we judge the thing to be so, because this is not implied in what was said before. A woman with child never says, that, going such a journey, she carried her child along with her. We know that, while it is in her womb, she must carry it along with her. There are some operations of mind that may be said to carry judgment in their womb, and can no more leave it behind than the pregnant woman can leave her child. Therefore, in speaking of such operations, it is not expressed.1

A fourth observation is, that some exercise of Edition: current; Page: [138] judgment is necessary in the formation of all abstract and general conceptions, whether more simple or more complex; in dividing, in defining, and, in general, in forming all clear and distinct conceptions of things, which are the only fit materials of reasoning.

These operations are allied to each other, and therefore I bring them under one observation. They are more allied to our rational nature than those mentioned in the last observation, and therefore are considered by themselves.

That I may not be mistaken, it may be observed that I do not say that abstract notions, or other accurate notions of things, after they have been formed, cannot be barely conceived without any exercise of judgment about them. I doubt not that they may: but what I say is, that, in their formation in the mind at first, there must be some exercise of judgment.

It is impossible to distinguish the different attributes belonging to the same subject, without judging that they are really different and distinguishable, and that they have that relation to the subject which logicians express, by saying that they may be predicated of it. We cannot generalise, without judging that the same attribute does or may belong to many individuals. It has been shewn that our simplest general notions are formed by these two operations of distinguishing Edition: current; Page: [139] and generalising; judgment therefore is exercised in forming the simplest general notions.

In those that are more complex, and which have been shewn to be formed by combining the more simple, there is another act of the judgment required; for such combinations are not made at random, but for an end; and judgment is employed in fitting them to that end. We form complex general notions for conveniency of arranging our thoughts in discourse and reasoning; and, therefore, of an infinite number of combinations that might be formed, we choose only those that are useful and necessary.

I add in general, that, without some degree of judgment, we can form no accurate and distinct notions of things; so that one province of judgment is, to aid us in forming clear and distinct conceptions of things, which are the only fit materials for reasoning.

This will probably appear to be a paradox to philosophers, who have always considered the formation of ideas of every kind as belonging to simple apprehension; and that the sole province of judgment is to put them together in affirmative or negative propositions; and therefore it requires some confirmation.

First, I think it necessarily follows, from what has been already said in this observation. For if, without some degree of judgment, a man can Edition: current; Page: [140] neither distinguish, nor divide, nor define, nor form any general notion, simple or complex, he surely, without some degree of judgment, cannot have in his mind the materials necessary to reasoning.

There cannot be any proposition in language which does not involve some general conception. The proposition, that I exist, which Des Cartes thought the first of all truths, and the foundation of all knowledge, cannot be conceived without the conception of existence, one of the most abstract general conceptions. A man cannot believe his own existence, or the existence of anything he sees or remembers, until he has so much judgment as to distinguish things that really exist from things which are only conceived. He sees a man six feet high; he conceives a man sixty feet high: he judges the first object to exist, because he sees it; the second he does not judge to exist, because he only conceives it. Now, I would ask, Whether he can attribute existence to the first object, and not to the second, without knowing what existence means? It is impossible.

How early the notion of existence enters into the mind, I cannot determine; but it must certainly be in the mind as soon as we can affirm of anything, with understanding, that it exists.

In every other proposition, the predicate, at least, must be a general notion—a predicable and an universal being one and the same. Besides this, Edition: current; Page: [141] every proposition either affirms or denies. And no man can have a distinct conception of a proposition, who does not understand distinctly the meaning of affirming or denying. But these are very general conceptions, and, as was before observed, are derived from judgment, as their source and origin.1

The necessity of some degree of judgment in forming accurate and distinct notions of things will farther appear, if we consider attentively what notions we can form, without any aid of judgment, of the objects of sense, of the operations of our own minds, or of the relations of things.

To begin with the objects of sense. It is acknowledged, on all hands, that the first notions we have of sensible objects are got by the external senses only, and probably before judgment is brought forth; but these first notions are neither simple, nor are they accurate and distinct: they are gross and indistinct, and, like the chaos, a rudis indigestaque moles. Before we can have any distinct notion of this mass, it must be analysed; the heterogeneous parts must be separated in our conception, and the simple elements, which before lay hid in the common mass, must first be distinguished, and then put together into one whole.

In this way it is that we form distinct notions even of the objects of sense; but this process of Edition: current; Page: [142] analysis and composition, by habit, becomes so easy, and is performed so readily, that we are apt to overlook it, and to impute the distinct notion we have formed of the object to the senses alone; and this we are the more prone to do because, when once we have distinguished the sensible qualities of the object from one another, the sense gives testimony to each of them.

If we should apply this reasoning to more complex objects of sense, the conclusion would be still more evident. A dog may be taught to turn a jack, but he can never be taught to have a distinct notion of a jack. He sees every part as well as a man; but the relation of the parts to one another and to the whole, he has not judgment to comprehend.

A distinct notion of an object, even of sense, is never got in an instant; but the sense performs its office in an instant. Time is not required to see it better, but to analyse it, to distinguish the different parts, and their relation to one another and to the whole.

Hence it is that, when any vehement passion or emotion hinders the cool application of judgment, we get no distinct notion of an object, even though the sense be long directed to it. A man who is put into a panic, by thinking he sees a ghost, may stare at it long without having any distinct notion of it; it is his understanding, and not Edition: current; Page: [143] his sense, that is disturbed by his horror. If he can lay that aside, judgment immediately enters upon its office, and examines the length and breadth, the colour, and figure, and distance of the object. Of these, while his panic lasted, he had no distinct notion, though his eyes were open all the time.

When the eye of sense is open, but that of judgment shut by a panic, or any violent emotion that engrosses the mind, we see things confusedly, and probably much in the same manner that brutes and perfect idiots do, and infants before the use of judgment.

Having said so much of the notions we get from the senses alone of the objects of sense, let us next consider what notions we can have from consciousness alone of the operations of our minds.

Mr Locke very properly calls consciousness an internal sense. It gives the like immediate knowledge of things in the mind—that is, of our own thoughts and feelings—as the senses give us of things external. There is this difference, however, that an external object may be at rest, and the sense may be employed about it for some time. But the objects of consciousness are never at rest: the stream of thought flows like a river, without stopping a moment; the whole train of thought passes in succession under the eye of consciousness, which is always employed about the present. But is it consciousness that analyses complex operations, Edition: current; Page: [144] distinguishes their different ingredients, and combines them in distinct parcels under general names? This surely is not the work of consciousness, nor can it be performed without reflection, recollecting and judging of what we were conscious of, and distinctly remember. This reflection does not appear in children. Of all the powers of the mind, it seems to be of the latest growth, whereas consciousness is coeval with the earliest.

Consciousness, being a kind of internal sense, can no more give us distinct and accurate notions of the operations of our minds, than the external senses can give of external objects. Reflection upon the operations of our minds is the same kind of operation with that by which we form distinct notions of external objects. They differ not in their nature, but in this only, that one is employed about external, and the other about internal objects; and both may, with equal propriety, be called reflection.

Mr Locke has restricted the word reflection to that which is employed about the operations of our minds, without any authority, as I think, from custom, the arbiter of language. For, surely, I may reflect upon what I have seen or heard, as well as upon what I have thought. The word, in its proper and common meaning, is equally applicable to objects of sense, and to objects of consciousness. He has likewise confounded reflection with Edition: current; Page: [145] consciousness, and seems not to have been aware that they are different powers, and appear at very different periods of life.

If that eminent philosopher had been aware of these mistakes about the meaning of the word reflection, he would, I think, have seen that, as it is by reflection upon the operations of our own minds that we can form any distinct and accurate notions of them, and not by consciousness without reflection, so it is by reflection upon the objects of sense, and not by the senses without reflection, that we can form distinct notions of them. Reflection upon anything, whether external or internal, makes it an object of our intellectual powers, by which we survey it on all sides, and form such judgments about it as appear to be just and true.

I proposed, in the third place, to consider our notions of the relations of things: and here I think, that, without judgment, we cannot have any notion of relations.

There are two ways in which we get the notion of relations. The first is, by comparing the related objects, when we have before had the conception of both. By this comparison, we perceive the relation, either immediately, or by a process of reasoning. That my foot is longer than my finger. I perceive immediately; and that three is the half of six. This immediate perception is immediate and intuitive judgment. That the angles at the base Edition: current; Page: [146] of an isosceles triangle are equal, I perceive by a process of reasoning, in which it will be acknowledged there is judgment.

Another way in which we get the notion of relations (which seems not to have occurred to Mr Locke) is, when, by attention to one of the related objects, we perceive or judge that it must, from its nature, have a certain relation to something else, which before, perhaps, we never thought of; and thus our attention to one of the related objects produces the notion of a correlate, and of a certain relation between them.

Thus, when I attend to colour, figure, weight, I cannot help judging these to be qualities which cannot exist without a subject; that is, something which is coloured, figured, heavy. If I had not perceived such things to be qualities, I should never have had any notion of their subject, or of their relation to it.

By attending to the operations of thinking, memory, reasoning, we perceive or judge that there must be something which thinks, remembers, and reasons, which we call the mind. When we attend to any change that happens in Nature, judgment informs us that there must be a cause of this change, which had power to produce it; and thus we get the notions of cause and effect, and of the relation between them. When we attend to body, we perceive that it cannot exist without space; hence we Edition: current; Page: [147] get the notion of space (which is neither an object of sense nor of consciousness), and of the relation which bodies have to a certain portion of unlimited space, as their place.

I apprehend, therefore, that all our notions of relations may more properly be ascribed to judgment as their source and origin, than to any other power of the mind. We must first perceive relations by our judgment, before we can conceive them without judging of them; as we must first perceive colours by sight, before we can conceive them without seeing them. I think Mr Locke, when he comes to speak of the ideas of relations, does not say that they are ideas of sensation or reflection, but only that they terminate in, and are concerned about, ideas of sensation or reflection.

The notions of unity and number are so abstract, that it is impossible they should enter into the mind until it has some degree of judgment. We see with what difficulty, and how slowly, children learn to use, with understanding, the names even of small numbers, and how they exult in this acquisition when they have attained it. Every number is conceived by the relation which it bears to unity, or to known combinations of units; and upon that account, as well as on account of its abstract nature, all distinct notions of it require some degree of judgment.

In its proper place, I shall have occasion to shew Edition: current; Page: [148] that judgment is an ingredient in all determinations of taste, in all moral determinations, and in many of our passions and affections. So that this operation, after we come to have any exercise of judgment, mixes with most of the operations of our minds, and, in analysing them, cannot be overlooked without confusion and error.1

§ 8.: Of Common Sense

All that is intended in this chapter is to explain the meaning of common sense, that it may not be treated, as it has been by some, as a new principle, or as a word without any meaning. I have endeavoured to shew that sense, in its most common, and therefore its most proper meaning, signifies judgment, though philosophers often use it in another meaning. From this it is natural to think that common sense should mean common judgment, and so it really does.

What the precise limits are which divide common judgment from what is beyond it on the one hand, and from what falls short of it on the other, may be difficult to determine; and men may agree in the meaning of the word who have different opinions about those limits, or who even never thought of fixing them. This is as intelligible as, that all Englishmen should mean the same thing by the county of York, though Edition: current; Page: [149] perhaps not a hundredth part of them can point out its precise limits.

Indeed, it seems to me, that common sense is as unambiguous a word and as well understood as the county of York. We find it in innumerable places in good writers; we hear it on innumerable occasions in conversation; and, as far as I am able to judge, always in the same meaning. And this is probably the reason why it is so seldom defined or explained.

Dr Johnson, in the authorities he gives, to shew that the word sense signifies understanding, soundness of faculties, strength of natural reason, quotes Dr Bentley for what may be called a definition of common sense, though probably not intended for that purpose, but mentioned accidentally: “God hath endowed mankind with power and abilities, which we call natural light and reason, and common sense.”1

It is absurd to conceive that there can be any opposition between reason and common sense. It is indeed the first-born of Reason; and, as they are commonly joined together in speech and in writing, they are inseparable in their nature.

We ascribe to reason two offices, or two degrees. The first is to judge of things self-evident; the second to draw conclusions that are not self-evident from those that are. The first of these Edition: current; Page: [150] is the province, and the sole province, of common sense; and, therefore, it coincides with reason in its whole extent, and is only another name for one branch or one degree of reason. Perhaps it may be said, Why then should you give it a particular name, since it is acknowledged to be only a degree of reason? It would be a sufficient answer to this, Why do you abolish a name which is to be found in the language of all civilized nations, and has acquired a right by prescription? Such an attempt is equally foolish and ineffectual. Every wise man will be apt to think that a name which is found in all languages as far back as we can trace them, is not without some use.

But there is an obvious reason why this degree of reason should have a name appropriated to it; and that is, that, in the greatest part of mankind, no other degree of reason is to be found. It is this degree that entitles them to the denomination of reasonable creatures. It is this degree of reason, and this only, that makes a man capable of managing his own affairs, and answerable for his conduct towards others. There is therefore the best reason why it should have a name appropriated to it.

These two degrees of reason differ in other respects, which would be sufficient to entitle them to distinct names.

The first is purely the gift of Heaven. And where Heaven has not given it, no education can Edition: current; Page: [151] supply the want. The second is learned by practice and rules, when the first is not wanting. A man who has common sense may be taught to reason. But, if he has not that gift, no teaching will make him able either to judge of first principles or to reason from them.

I have only this farther to observe, that the province of common sense is more extensive in refutation than in confirmation. A conclusion drawn by a train of just reasoning from true principles cannot possibly contradict any decision of common sense, because truth will always be consistent with itself. Neither can such a conclusion receive any confirmation from common sense, because it is not within its jurisdiction.

But it is possible that, by setting out from false principles, or by an error in reasoning, a man may be led to a conclusion that contradicts the decisions of common sense. In this case, the conclusion is within the jurisdiction of common sense, though the reasoning on which it was grounded be not; and a man of common sense may fairly reject the conclusion without being able to shew the error of the reasoning that led to it.

Thus, if a mathematician, by a process of intricate demonstration, in which some false step was made, should be brought to this conclusion, that two quantities, which are both equal to a third, are not equal to each other, a man of common sense, Edition: current; Page: [152] without pretending to be a judge of the demonstration, is well entitled to reject the conclusion, and to pronounce it absurd.1

§ 9.: The First Principles of Contingent Truths

It is necessary that the first principles of knowledge be distinguished from other truths, and presented to view, that they may be sifted and examined on all sides. In order to this end, I shall attempt a detail of those I take to be such, and of the reasons why I think them entitled to that character.

If the enumeration should appear to some redundant, to others deficient, and to others both—if things which I conceive to be first principles, should to others appear to be vulgar errors, or to be truths which derive their evidence from other truths, and therefore not first principles—in these things every man must judge for himself. I shall rejoice to see an enumeration more perfect in any or in all of those respects; being persuaded that the agreement of men of judgment and candour in first principles would be of no less consequence to the advancement of knowledge in general, than the agreement of mathematicians in the axioms of geometry has been to the advancement of that science.

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The truths that fall within the compass of human knowledge, whether they be self-evident, or deduced from those that are self-evident, may be reduced to two classes. They are either necessary and immutable truths, whose contrary is impossible; or they are contingent and mutable, depending upon some effect of will and power, which had a beginning, and may have an end.

That a cone is the third part of a cylinder of the same base and the same altitude, is a necessary truth. It depends not upon the will and power of any being. It is immutably true, and the contrary impossible. That the sun is the centre about which the earth, and the other planets of our system, perform their revolutions, is a truth; but it is not a necessary truth. It depends upon the power and will of that Being who made the sun and all the planets, and who gave them those motions that seemed best to him.

As the minds of men are occupied much more about truths that are contingent than about those that are necessary, I shall first endeavour to point out the principles of the former kind.

1. First, then, I hold, as a first principle, the existence of everything of which I am conscious.

This, I think, is the only principle of common sense that has never directly been called in question. It seems to be so firmly rooted in the minds of men, as to retain its authority with the greatest Edition: current; Page: [154] sceptics. Mr Hume, after annihilating body and mind, time and space, action and causation, and even his own mind, acknowledges the reality of the thoughts, sensations, and passions of which he is conscious.

2. Another first principle, I think, is, That the thoughts of which I am conscious, are the thoughts of a being which I call myself, my mind, my person.

The thoughts and feelings of which we are conscious are continually changing, and the thought of this moment is not the thought of the last; but something which I call myself, remains under this change of thought. This self has the same relation to all the successive thoughts I am conscious of—they are all my thoughts; and every thought which is not my thought, must be the thought of some other person.

If any man asks a proof of this, I confess I can give none; there is an evidence in the proposition itself which I am unable to resist. Shall I think that thought can stand by itself without a thinking being? or that ideas can feel pleasure or pain? My nature dictates to me that it is impossible.

3. Another first principle I take to be—That those things did really happen which I distinctly remember.

This has one of the surest marks of a first principle; for no man ever pretended to prove it, and yet no man in his wits calls it in question: the testimony Edition: current; Page: [155] of memory, like that of consciousness, is immediate; it claims our assent upon its own authority.

4. Another first principle is, Our own personal identity and continued existence, as far back as we remember anything distinctly.

This we know immediately, and not by reasoning. It seems, indeed, to be a part of the testimony of memory. Everything we remember has such a relation to ourselves as to imply necessarily our existence at the time remembered.

5. Another first principle is, That those things do really exist which we distinctly perceive by our senses, and are what we perceive them to be.

It is too evident to need proof, that all men are by nature led to give implicit faith to the distinct testimony of their senses, long before they are capable of any bias from prejudices of education or of philosophy.

6. Another first principle, I think, is, That we have some degree of power over our actions, and the determinations of our will.

All power must be derived from the fountain of power, and of every good gift. Upon His good pleasure its continuance depends, and it is always subject to His control.

Beings to whom God has given any degree of power, and understanding to direct them to the proper use of it, must be accountable to their Maker. But those who are intrusted with no power Edition: current; Page: [156] can have no account to make; for all good conduct consists in the right use of power; all bad conduct in the abuse of it.

7. Another first principle is—That the natural faculties, by which we distinguish truth from error, are not fallacious. If any man should demand a proof of this, it is impossible to satisfy him. For, suppose it should be mathematically demonstrated, this would signify nothing in this case; because, to judge of a demonstration, a man must trust his faculties, and take for granted the very thing in question.

8. Another first principle relating to existence, is, That there is life and intelligence in our fellow-men with whom we converse.

9. Another first principle I take to be, that certain features of the countenance, sounds of the voice, and gestures of the body, indicate certain thoughts and dispositions of mind.

10. Another first principle appears to me to be—That there is a certain regard due to human testimony in matters of fact, and even to human authority in matters of opinion.

11. There are many events depending upon the will of man, in which there is a self-evident probability, greater or less, according to circumstances.

12. The last principle of contingent truths I mention is, That, in the phænomena of nature, what is to be will probably be like to what has been in similar circumstances.

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We must have this conviction as soon as we are capable of learning anything from experience; for all experience is grounded upon a belief that the future will be like the past. Take away this principle, and the experience of an hundred years makes us no wiser with regard to what is to come.

This is one of those principles which, when we grow up and observe the course of nature, we can confirm by reasoning. We perceive that Nature is governed by fixed laws, and that, if it were not so, there could be no such thing as prudence in human conduct; there would be no fitness in any means to promote an end; and what, on one occasion, promoted it, might as probably, on another occasion, obstruct it.

But the principle is necessary for us before we are able to discover it by reasoning, and therefore is made a part of our constitution, and produces its effects before the use of reason.

I do not at all affirm, that those I have mentioned are all the first principles from which we may reason concerning contingent truths. Such enumerations, even when made after much reflection, are seldom perfect.1

§ 10.: First Principles of Necessary Truths

About most of the first principles of necessary truths there has been no dispute, and therefore it is Edition: current; Page: [158] the less necessary to dwell upon them. It will be sufficient to divide them into different classes; to mention some, by way of specimen, in each class; and to make some remarks on those of which the truth has been called in question.

They may, I think, most properly be divided according to the sciences to which they belong.

1. There are some first principles that may be called grammatical: such as, That every adjective in a sentence must belong to some substantive expressed or understood; that every complete sentence must have a verb.

2. There are logical axioms: such as, That any contexture of words, which does not make a proposition, is neither true nor false; That every proposition is either true or false; That no proposition can be both true and false at the same time; That reasoning in a circle proves nothing; That whatever may be truly affirmed of a genus, may be truly affirmed of all the species, and all the individuals belonging to that genus.

3. Every one knows there are mathematical axioms. Mathematicians have, from the days of Euclid, very wisely laid down the axioms or first principles on which they reason. And the effect which this appears to have had upon the stability and happy progress of this science, gives no small encouragement to attempt to lay the foundation of other sciences in a similar manner, as far as we are able.

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4. I think there are axioms, even in matters of taste. Notwithstanding the variety found among men in taste, there are, I apprehend, some common principles, even in matters of this kind. I never heard of any man who thought it a beauty in a human face to want a nose, or an eye, or to have the mouth on one side.

That an unjust action has more demerit than an ungenerous one: That a generous action has more merit than a merely just one: That no man ought to be blamed for what it was not in his power to hinder: That we ought not to do to others what we would think unjust or unfair to be done to us in like circumstances. These are moral axioms, and many others might be named which appear to me to have no less evidence than those of mathematics.

Some perhaps may think that our determinations, either in matters of taste or in morals, ought not to be accounted necessary truths: That they are grounded upon the constitution of that faculty which we call taste, and of that which we call the moral sense or conscience; which faculties might have been so constituted as to have given determinations different, or even contrary to those they now give: That, as there is nothing sweet or bitter in itself, but according as it agrees or disagrees with the external sense called taste; so there is nothing beautiful or ugly in itself, but according as it agrees or disagrees with the internal Edition: current; Page: [160] sense, which we also call taste; and nothing morally good or ill in itself, but according as it agrees or disagrees with our moral sense.

This indeed is a system, with regard to morals and taste, which hath been supported in modern times by great authorities. And if this system be true, the consequence must be, that there can be no principles, either of taste or of morals, that are necessary truths. For, according to this system, all our determinations, both with regard to matters of taste, and with regard to morals, are reduced to matters of fact—I mean to such as these, that by our constitution we have on such occasions certain agreeable feelings, and on other occasions certain disagreeable feelings.

But I cannot help being of a contrary opinion, being persuaded that a man who determined that polite behaviour has great deformity, and that there is great beauty in rudeness and ill-breeding, would judge wrong, whatever his feelings were.

In like manner, I cannot help thinking that a man who determined that there is more moral worth in cruelty, perfidy, and injustice, than in generosity, justice, prudence, and temperance, would judge wrong, whatever his constitution was.

And, if it be true that there is judgment in our determinations of taste and of morals, it must be granted that what is true or false in morals, or in matters of taste, is necessarily so. For this reason, Edition: current; Page: [161] I have ranked the first principles of morals and of taste under the class of necessary truths.

6. The last class of first principles I shall mention, we may call metaphysical.

I shall particularly consider three of these, because they have been called in question by Mr Hume.

The first is, That the qualities which we perceive by our senses must have a subject, which we call body, and that the thoughts we are conscious of must have a subject, which we call mind.

The second metaphysical principle I mention is—That whatever begins to exist, must have a cause which produced it.

The last metaphysical principle I mention, which is opposed by the same author, is, That design and intelligence in the cause may be inferred, with certainty, from marks or signs of it in the effect.1


§ 1.: Of Benevolent Affection in General

There are various principles of action in man, which have persons for their immediate object, and imply, in their very nature, our being well or ill affected to some person, or, at least, to some animated being.

Such principles, I shall call by the general name Edition: current; Page: [162] of affections, whether they dispose us to do good or hurt to others.

The principles which lead us immediately to desire the good of others, and those that lead us to desire their hurt, agree in this, that persons, and not things, are their immediate object. Both imply our being some way affected towards the person. They ought, therefore, to have some common name to express what is common in their nature; and I know no name more proper for this than affection.

Taking affection, therefore, in this extensive sense, our affections are very naturally divided into benevolent and malevolent, according as they imply our being well or ill affected towards their object.

There are some things common to all benevolent affections, others wherein they differ.

They differ both in the feeling or sensation, which is an ingredient in all of them, and in the objects to which they are directed.

They all agree in two things—to wit, That the feeling which accompanies them is agreeable; and, That they imply a desire of good and happiness to their object.

A thing may be desired either on its own account, or as the means in order to something else. That only can properly be called an object of desire, which is desired upon its own account; and it is Edition: current; Page: [163] only such desires that I call principles of action. When anything is desired as the means only, there must be an end for which it is desired; and the desire of the end is, in this case, the principle of action. The means are desired only as they tend to that end; and, if different, or even contrary means, tended to the same end, they would be equally desired.

On this account, I consider those affections only as benevolent, where the good of the object is desired ultimately, and not as the means only, in order to something else.

To say that we desire the good of others, only in order to procure some pleasure or good to ourselves, is to say that there is no benevolent affection in human nature.

This, indeed, has been the opinion of some philosophers, both in ancient and in later times. I intend not to examine this opinion in this place, conceiving it proper to give that view of the principles of action in man, which appears to me to be just, before I examine the systems wherein they have been mistaken or misrepresented.

I observe only at present, that it appears as unreasonable to resolve all our benevolent affections into self-love, as it would be to resolve hunger and thirst into self-love.

These appetites are necessary for the preservation of the individual. Benevolent affections are no Edition: current; Page: [164] less necessary for the preservation of society among men, without which man would become an easy prey to the beasts of the field.

We are placed in this world by the Author of our being, surrounded with many objects that are necessary or useful to us, and with many that may hurt us. We are led, not by reason and self-love only, but by many instincts, and appetites, and natural desires to seek the former and to avoid the latter.

But of all the things of this world, man may be the most useful or the most hurtful to man. Every man is in the power of every man with whom he lives. Every man has power to do much good to his fellow-men, and to do more hurt.

We cannot live without the society of men; and it would be impossible to live in society, if men were not disposed to do much of that good to men, and but little of that hurt, which it is in their power to do.

But how shall this end, so necessary to the existence of human society, and consequently to the existence of the human species, be accomplished?

If we judge from analogy, we must conclude that in this, as in other parts of our conduct, our rational principles are aided by principles of an inferior order, similar to those by which many brute animals live in society with their species; and that, by means of such principles, that degree of regularity Edition: current; Page: [165] is observed, which we find in all societies of men, whether wise or foolish, virtuous or vicious.

The benevolent affections planted in human nature appear therefore no less necessary for the preservation of the human species, than the appetites of hunger and thirst.1

§ 2.: There are Rational Principles of Action in Man

Mechanical principles of action produce their effect without any will or intention on our part. We may, by a voluntary effort, hinder the effect; but, if it be not hindered by will and effort, it is produced without them.

Animal principles of action require intention and will in their operation, but not judgment. They are, by ancient moralists, very properly called cæcæ cupidines, blind desires.

Having treated of these two classes, I proceed to the third—the rational principles of action in man; which have that name, because they can have no existence in beings not endowed with reason, and, in all their exertions, require, not only intention and will, but judgment or reason.

That talent which we call Reason, by which men that are adult and of a sound mind are distinguished Edition: current; Page: [166] from brutes, idiots, and infants, has, in all ages, among the learned and unlearned, been conceived to have two offices—to regulate our belief, and to regulate our actions and conduct.

Whatever we believe, we think agreeable to reason, and, on that account, yield our assent to it. Whatever we disbelieve, we think contrary to reason, and, on that account, dissent from it. Reason, therefore, is allowed to be the principle by which our belief and opinions ought to be regulated.

But reason has been no less universally conceived to be a principle by which our actions ought to be regulated.

To act reasonably, is a phrase no less common in all languages, than to judge reasonably. We immediately approve of a man’s conduct, when it appears that he had good reason for what he did. And every action we disapprove, we think unreasonable, or contrary to reason.

A way of speaking so universal among men, common to the learned and the unlearned in all nations and in all languages, must have a meaning. To suppose it to be words without meaning, is to treat, with undue contempt, the common sense of mankind.

Supposing this phrase to have a meaning, we may consider in what way reason may serve to regulate human conduct, so that some actions of men are to be denominated reasonable, and others unreasonable.

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I take it for granted, that there can be no exercise of Reason without Judgment, nor, on the other hand, any judgment of things, abstract and general, without some degree of reason.

If, therefore, there be any principles of action in the human constitution, which, in their nature, necessarily imply such judgment, they are the principles which we may call rational, to distinguish them from animal principles, which imply desire and will, but not judgment.

Every deliberate human actions must be done either as the means, or as an end; as the means to some end, to which it is subservient, or as an end, for its own sake, and without regard to anything beyond it.

That it is a part of the office of reason to determine what are the proper means to any end which we desire, no man ever denied. But some philosophers, particularly Mr Hume, think that it is no part of the office of reason to determine the ends we ought to pursue, or the preference due to one end above another. This, he thinks, is not the office of reason, but of taste or feeling.

If this be so, reason cannot, with any propriety, be called a principle of action. Its office can only be to minister to the principles of action, by discovering the means of their gratification. Accordingly, Mr Hume maintains, that reason is no principle of action; but that it is, and ought to be, the servant of the passions.

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I shall endeavour to shew that, among the various ends of human actions, there are some, of which, without reason, we could not even form a conception; and that, as soon as they are conceived, a regard to them is, by our constitution, not only a principle of action, but a leading and governing principle, to which all our animal principles are subordinate, and to which they ought to be subject.

These I shall call rational principles; because they can exist only in beings endowed with reason, and because, to act from these principles, is what has always been meant by acting according to reason.

The ends of human actions I have in view, are two—to wit, What is good for us upon the whole, and What appears to be our duty. They are very strictly connected, lead to the same course of conduct, and co-operate with each other; and, on that account, have commonly been comprehended under one name—that of reason. But, as they may be disjoined, and are really distinct principles of action, I shall consider them separately.1

§ 3.: Of Regard to Our Good on the Whole

It will not be denied that man, when he comes to years of understanding, is led, by his rational nature, to form the conception of what is good for him upon the whole.

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How early in life this general notion of good enters into the mind, I cannot pretend to determine. It is one of the most general and abstract notions we form.

Whatever makes a man more happy or more perfect, is good, and is an object of desire as soon as we are capable of forming the conception of it. The contrary is ill, and is an object of aversion.

In the first part of life, we have many enjoyments of various kinds; but very similar to those of brute-animals.

They consist in the exercise of our senses and powers of motion, the gratification of our appetites, and the exertions of our kind affections. These are chequered with many evils of pain, and fear, and disappointment, and sympathy with the sufferings of others.

But the goods and evils of this period of life are of short duration, and soon forgot. The mind, being regardless of the past, and unconcerned about the future, we have then no other measure of good but the present desire; no other measure of evil but the present aversion.

Every animal desire has some particular and present object, and looks not beyond that object to its consequences, or to the connections it may have with other things.

The present object, which is most attractive, or excites the strongest desire, determines the choice, Edition: current; Page: [170] whatever be its consequences. The present evil that presses most, is avoided, though it should be the road to a greater good to come, or the only way to escape a greater evil. This is the way in which brutes act, and the way in which men must act, till they come to the use of reason.

As we grow up to understanding, we extend our view both forward and backward. We reflect upon what is past, and, by the lamp of experience, discern what will probably happen in time to come. We find that many things which we eagerly desired, were too dearly purchased, and that things grievous for the present, like nauseous medicines, may be salutary in the issue.

We learn to observe the connexions of things, and the consequences of our actions; and, taking an extended view of our existence, past, present, and future, we correct our first notions of good and ill, and form the conception of what is good or ill upon the whole; which must be estimated, not from the present feeling, or from the present animal desire or aversion, but from a due consideration of its consequences, certain or probable, during the whole of our existence.

That which, taken with all its discoverable connexions and consequences, brings more good than ill, I call good upon the whole.

That brute-animals have any conception of this good, I see no reason to believe. And it is evident Edition: current; Page: [171] that man cannot have the conception of it, till reason is so far advanced that he can seriously reflect upon the past, and take a prospect of the future part of his existence.

It appears, therefore, that the very conception of what is good or ill for us upon the whole, is the offspring of reason, and can be only in beings endowed with reason. And if this conception give rise to any principle of action in man, which he had not before, that principle may very properly be called a rational principle of action.

I observe, in the next place—That as soon as we have the conception of what is good or ill for us upon the whole, we are led, by our constitution, to seek the good and avoid the ill; and this becomes not only a principle of action, but a leading or governing principle, to which all our animal principles ought to be subordinate.

To prefer a greater good, though distant, to a less that is present; to choose a present evil, in order to avoid a greater evil, or to obtain a greater good, is, in the judgment of all men, wise and reasonable conduct; and, when a man acts the contrary part, all men will acknowledge that he acts foolishly and unreasonably. Nor will it be denied, that, in innumerable cases in common life, our animal principles draw us one way, while a regard to what is good on the whole, draws us the contrary way. Thus the flesh lusteth Edition: current; Page: [172] against the spirit, and the spirit against the flesh, and these two are contrary. That in every conflict of this kind the rational principle ought to prevail, and the animal to be subordinate, is too evident to need, or to admit of proof.

Thus, I think, it appears, that, to pursue what is good upon the whole, and to avoid what is ill upon the whole, is a rational principle of action grounded upon our constitution as reasonable creatures.

It appears that it is not without just cause, that this principle of action has in all ages been called reason, in opposition to our animal principles, which in common language are called by the general name of the passions.

The first not only operates in a calm and cool manner, like reason, but implies real judgment in all its operations. The second—to wit, the passions—are blind desires of some particular object, without any judgment or consideration, whether it be good for us upon the whole, or ill.

It appears also, that the fundamental maxim of prudence, and of all good morals—That the passions ought, in all cases, to be under the dominion of reason—is not only self-evident, when rightly understood, but is expressed according to the common use and propriety of language.1

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§ 4.: Of the Notion of Duty, Rectitude, Moral Obligation

A being endowed with the animal principles of action only may be capable of being trained to certain purposes by discipline, as we see many brute-animals are, but would be altogether incapable of being governed by law.

The subject of law must have the conception of a general rule of conduct, which, without some degree of reason, he cannot have. He must likewise have a sufficient inducement to obey the law, even when his strongest animal desires draw him the contrary way.

This inducement may be a sense of interest, or a sense of duty, or both concurring.

These are the only principles I am able to conceive, which can reasonably induce a man to regulate all his actions according to a certain general rule or law. They may therefore be justly called the rational principles of action, since they can have no place but in a being endowed with reason, and since it is by them only that man is capable either of political or of moral government.

Without them human life would be like a ship at sea without hands, left to be carried by winds and tides as they happen. It belongs to the rational part of our nature to intend a certain port, as the end of the voyage of life; to take the advantage Edition: current; Page: [174] of winds and tides when they are favourable, and to bear up against them when they are unfavourable.

A sense of interest may induce us to do this, when a suitable reward is set before us. But there is a nobler principle in the constitution of man, which, in many cases, gives a clearer and more certain rule of conduct, than a regard merely to interest would give, and a principle, without which man would not be a moral agent.

A man is prudent when he consults his real interest; but he cannot be virtuous, if he has no regard to duty.

I proceed now to consider this regard to Duty as a rational principle of action in man, and as that principle alone by which he is capable either of virtue or vice.

I shall first offer some observations with regard to the general notion of duty, and its contrary, or of right and wrong in human conduct, and then consider, how we come to judge and determine certain things in human conduct to be right, and others to be wrong.

With regard to the notion or conception of Duty, I take it to be too simple to admit of a logical definition.

We can define it only by synonymous words or phrases, or by its properties and necessary concomitants, as when we say that it is what we ought Edition: current; Page: [175] to do—what is fair and honest—what is approvable—what every man professes to be the rule of his conduct—what all men praise—and, what is in itself laudable, though no man should praise it.

I observe, in the next place, That the notion of duty cannot be resolved into that of interest, or what is most for our happiness.

Every man may be satisfied of this who attends to his own conceptions, and the language of all mankind shews it. When I say, This is my interest, I mean one thing; when I say, It is my duty, I mean another thing. And, though the same course of action, when rightly understood, may be both my duty and my interest, the conceptions are very different. Both are reasonable motives to action, but quite distinct in their nature.

I presume it will be granted, that, in every man of real worth, there is a principle of honour, a regard to what is honourable or dishonourable, very distinct from a regard to his interest. It is folly in a man to disregard his interest, but to do what is dishonourable, is baseness. The first may move our pity, or, in some cases, our contempt; but the last provokes our indignation.

As these two principles are different in their nature, and not resolvable into one, so the principle of honour is evidently superior in dignity to that of interest.

No man would allow him to be a man of honour Edition: current; Page: [176] who should plead his interest to justify what he acknowledged to be dishonourable; but to sacrifice interest to honour never costs a blush.

It likewise will be allowed by every man of honour, that this principle is not to be resolved into a regard to our reputation among men, otherwise the man of honour would not deserve to be trusted in the dark. He would have no aversion to lie, or cheat, or play the coward, when he had no dread of being discovered.

I take it for granted, therefore, that every man of real honour feels an abhorrence of certain actions, because they are in themselves base, and feels an obligation to certain other actions, because they are in themselves what honour requires, and this independently of any consideration of interest or reputation.

This is an immediate moral obligation. This principle of honour, which is acknowledged by all men who pretend to character, is only another name for what we call a regard to duty, to rectitude, to propriety of conduct. It is a moral obligation which obliges a man to do certain things because they are right, and not to do other things because they are wrong.

Ask the man of honour why he thinks himself obliged to pay a debt of honour? The very question shocks him. To suppose that he needs any other inducement to do it but the principle Edition: current; Page: [177] of honour, is to suppose that he has no honour, no worth, and deserves no esteem.

There is, therefore, a principle in man, which, when he acts according to it, gives him a consciousness of worth, and, when he acts contrary to it, a sense of demerit.

From the varieties of education, of fashion, of prejudices, and of habits, men may differ much in opinion with regard to the extent of this principle, and of what it commands and forbids; but the notion of it, as far as it is carried, is the same in all. It is that which gives a man real worth, and is the object of moral approbation.

Men of rank call it honour, and too often confine it to certain virtues that are thought most essential to their rank. The vulgar call it honesty, probity, virtue, conscience. Philosophers have given it the names of the moral sense, the moral faculty, rectitude.

If we examine the abstract notion of Duty, or Moral Obligation, it appears to be neither any real quality of the action considered by itself, nor of the agent considered without respect to the action, but a certain relation between the one and the other.

When we say a man ought to do such a thing, the ought, which expresses the moral obligation, has a respect, on the one hand, to the person who ought; and, on the other, to the action which he ought to do. Those two correlates are essential to every moral obligation; take away either, and it has no Edition: current; Page: [178] existence. So that, if we seek the place of moral obligation among the categories, it belongs to the category of relation.

There are many relations of things, of which we have the most distinct conception, without being able to define them logically. Equality and proportion are relations between quantities, which every man understands, but no man can define.

Moral obligation is a relation of its own kind, which every man understands, but is, perhaps, too simple to admit of logical definition. Like all other relations, it may be changed or annihilated by a change in any of the two related things—I mean the agent or the action.

Perhaps it may not be improper to point out briefly the circumstances, both in the action and in the agent, which are necessary to constitute moral obligation. The universal agreement of men in these, shews that they have one and the same notion of it.

With regard to the action, it must be a voluntary action, or prestation of the person obliged, and not of another. There can be no moral obligation upon a man to be six feet high. Nor can I be under a moral obligation that another person should do such a thing. His actions must be imputed to himself, and mine only to me, either for praise or blame.

I need hardly mention, that a person can be under Edition: current; Page: [179] a moral obligation, only to things within the sphere of his natural power.

As to the party obliged, it is evident there can be no moral obligation upon an inanimate thing. To speak of moral obligation upon a stone or a tree is ridiculous, because it contradicts every man’s notion of moral obligation.

The person obliged must have understanding and will, and some degree of active power. He must not only have the natural faculty of understanding, but the means of knowing his obligation. An invincible ignorance of this destroys all moral obligation.

The opinion of the agent in doing the action gives it its moral denomination. If he does a materially good action, without any belief of its being good, but from some other principle, it is no good action in him. And if he does it with the belief of its being ill, it is ill in him.

Thus, if a man should give to his neighbour a potion which he really believes will poison him, but which, in the event, proves salutary, and does much good; in moral estimation, he is a poisoner, and not a benefactor.

These qualifications of the action and of the agent, in moral obligation, are self-evident; and the agreement of all men in them shews that all men have the same notion, and a distinct notion of moral obligation.

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We are next to consider, how we learn to judge and determine, that this is right, and that is wrong.

The abstract notion of moral good and ill would be of no use to direct our life, if we had not the power of applying it to particular actions, and determining what is morally good, and what is morally ill.

Some philosophers, with whom I agree, ascribe this to an original power or faculty in man, which they call the Moral Sense, the Moral Faculty, Conscience.

In its dignity it is, without doubt, far superior to every other power of the mind; but there is this analogy between it and the external senses, That, as by them we have not only the original conceptions of the various qualities of bodies, but the original judgment that this body has such a quality, that such another; so by our moral faculty, we have both the original conceptions of right and wrong in conduct, of merit and demerit, and the original judgments that this conduct is right, that is wrong; that this character has worth, that demerit.

The testimony of our moral faculty, like that of the external senses, is the testimony of nature, and we have the same reason to rely upon it.

The truths immediately testified by the external senses are the first principles from which we reason, Edition: current; Page: [181] with regard to the material world, and from which all our knowledge of it is deduced.

The truths immediately testified by our moral faculty, are the first principles of all moral reasoning, from which all our knowledge of our duty must be deduced.

By moral reasoning, I understand all reasoning that is brought to prove that such conduct is right, and deserving of moral approbation; or that it is wrong; or that it is indifferent, and, in itself, neither morally good nor ill.

I think, all we can properly call moral judgments, are reducible to one or other of these, as all human actions, considered in a moral view, are either good, or bad, or indifferent.

I know the term moral reasoning is often used by good writers in a more extensive sense; but, as the reasoning I now speak of is of a peculiar kind, distinct from all others, and, therefore, ought to have a distinct name, I take the liberty to limit the name of moral reasoning to this kind.

Let it be understood, therefore, that in the reasoning I call moral, the conclusion always is, That something in the conduct of moral agents is good or bad, in a greater or a less degree, or indifferent.

All reasoning must be grounded on first principles. This holds in moral reasoning, as in all other kinds. There must, therefore, be in morals, as in all other sciences, first or self-evident principles, on which Edition: current; Page: [182] all moral reasoning is grounded, and on which it ultimately rests. From such self-evident principles, conclusions may be drawn synthetically with regard to the moral conduct of life; and particular duties or virtues may be traced back to such principles, analytically. But, without such principles, we can no more establish any conclusion in morals, than we can build a castle in the air, without any foundation.1

§ 5.: Observations concerning Conscience

I shall now conclude this essay with some observations concerning this power of the mind which we call Conscience, by which its nature may be better understood.

The first is, That, like all our other powers, it comes to maturity by insensible degrees, and may be much aided in its strength and vigour by proper culture.

A second observation is, That Conscience is peculiar to man. We see not a vestige of it in brute animals. It is one of those prerogatives by which we are raised above them.

The next observation is—That Conscience is evidently intended by nature to be the immediate guide and director of our conduct, after we arrive at the years of understanding.

It judges of every action before it is done. For Edition: current; Page: [183] we can rarely act so precipitately but we have the consciousness that what we are about to do is right, or wrong, or indifferent. Like the bodily eye, it naturally looks forward, though its attention may be turned back to the past.

To conceive, as some seem to have done, that its office is only to reflect on past actions, and to approve or disapprove, is, as if a man should conceive that the office of his eyes is only to look back upon the road he has travelled, and to see whether it be clean or dirty; a mistake which no man can make who has made the proper use of his eyes.

Conscience prescribes measures to every appetite, affection, and passion, and says to every other principle of action—So far thou mayest go, but no farther.

We may indeed transgress its dictates, but we cannot transgress them with innocence, nor even with impunity.

We condemn ourselves, or, in the language of scripture, our heart condemns us, whenever we go beyond the rules of right and wrong which conscience prescribes.

Other principles of action may have more strength, but this only has authority. Its sentence makes us guilty to ourselves, and guilty in the eyes of our Maker, whatever other principle may be set in opposition to it.

It is evident, therefore, that this principle has, Edition: current; Page: [184] from its nature, an authority to direct and determine with regard to our conduct; to judge, to acquit, or to condemn, and even to punish; an authority which belongs to no other principle of the human mind.

It is the candle of the Lord set up within us, to guide our steps. Other principles may urge and impel, but this only authorizes. Other principles ought to be controlled by this; this may be, but never ought to be controlled by any other, and never can be with innocence.

The authority of conscience over the other active principles of the mind, I do not consider as a point that requires proof by argument, but as self-evident. For it implies no more than this—That in all cases a man ought to do his duty. He only who does in all cases what he ought to do, is the perfect man.

The last observation is—That the Moral Faculty or Conscience is both an Active and an Intellectual power of the mind.

It is an active power, as every truly virtuous action must be more or less influenced by it. Other principles may concur with it, and lead the same way; but no action can be called morally good, in which a regard to what is right has not some influence. Thus, a man who has no regard to justice, may pay his just debt, from no other motive but that he may not be thrown into prison. In this action there is no virtue at all.

The moral principle, in particular cases, may be Edition: current; Page: [185] opposed by any of our animal principles. Passion or appetite may urge to what we know to be wrong. In every instance of this kind, the moral principle ought to prevail, and the more difficult its conquest is, it is the more glorious.

In some cases, a regard to what is right may be the sole motive, without the concurrence or opposition of any other principle of action; as when a judge or an arbiter determines a plea between two different persons, solely from a regard to justice.

Thus we see that conscience, as an active principle, sometime concurs with other active principles, sometimes opposes them, and sometimes is the sole principle of action.

I conclude with observing, That conscience, or the moral faculty, is likewise an intellectual power.

By it solely we have the original conceptions or ideas of right and wrong in human conduct. And of right and wrong there are not only many different degrees, by many different species. Justice and injustice, gratitude and ingratitude, benevolence and malice, prudence and folly, magnanimity and meanness, decency and indecency, are various moral forms, all comprehended under the general notion of right and wrong in conduct, all of them objects of moral approbation or disapprobation, in a greater or a less degree.

The conception of these, as moral qualities, we have by our moral faculty; and by the same Edition: current; Page: [186] faculty, when we compare them together, we perceive various moral relations among them. Thus, we perceive that justice is entitled to a small degree of praise, but injustice to a high degree of blame; and the same may be said of gratitude and its contrary. When justice and gratitude interfere, gratitude must give place to justice, and unmerited beneficence must give place to both.

Many such relations between the various moral qualities compared together, are immediately discerned by our moral faculty. A man needs only to consult his own heart to be convinced of them.

All our reasonings in morals, in natural jurisprudence, in the law of nations, as well as our reasonings about the duties of natural religion, and about the moral government of the Deity, must be grounded upon the dictates of our moral faculty, as first principles.

As this faculty, therefore, furnishes the human mind with many of its original conceptions or ideas, as well as with the first principles of many important branches of human knowledge, it may justly be accounted an intellectual as well as an active power of the mind.1

§ 6.: That Moral Approbation implies a Real Judgment

The approbation of good actions, and disapprobation of bad, are so familiar to every man come to Edition: current; Page: [187] years of understanding, that it seems strange there should be any dispute about their nature.

Whether we reflect upon our own conduct, or attend to the conduct of others with whom we live, or of whom we hear or read, we cannot help approving of some things, disapproving of others, and regarding many with perfect indifference.

These operations of our minds we are conscious of every day and almost every hour we live. Men of ripe understanding are capable of reflecting upon them, and of attending to what passes in their own thoughts on such occasions; yet, for half a century, it has been a serious dispute among philosophers what this approbation and disapprobation is, Whether there be a real judgment included in it, which, like all other judgments, must be true or false; or, Whether it include no more but some agreeable or uneasy feeling, in the person who approves or disapproves.

Mr Hume observes very justly, that this is a controversy started of late. Before the modern system of Ideas and Impressions was introduced, nothing would have appeared more absurd than to say, that when I condemn a man for what he has done, I pass no judgment at all about the man, but only express some uneasy feeling in myself.

Nor did the new system produce this discovery at once, but gradually, by several steps, according as its consequences were more accurately traced, Edition: current; Page: [188] and its spirit more thoroughly imbibed by successive philosophers.

Des Cartes and Mr Locke went no farther than to maintain that the Secondary Qualities of body—Heat and Cold, Sound, Colour, Taste, and Smell—which we perceive and judge to be in the external object, are mere feelings or sensations in our minds, there being nothing in bodies themselves to which these names can be applied; and that the office of the external senses is not to judge of external things, but only to give us ideas of sensations, from which we are by reasoning to deduce the existence of a material world without us, as well as we can.

Arthur Collier and Bishop Berkeley discovered, from the same principles, that the Primary, as well as the Secondary, Qualities of bodies, such as Extension, Figure, Solidity, Motion, are only sensations in our minds; and, therefore, that there is no material world without us at all.

The same philosophy, when it came to be applied to matters of taste, discovered that beauty and deformity are not anything in the objects, to which men, from the beginning of the world, ascribed them, but certain feelings in the mind of the spectator.

The next step was an easy consequence from all the preceding, that Moral Approbation and Disapprobation are not Judgments, which must be true or false, but barely agreeable and uneasy Feelings or Sensations.

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Mr Hume made the last step in this progress, and crowned the system by what he calls his hypothesis—to wit, That Belief is more properly an act of the Sensitive than of the Cogitative part of our nature.

Beyond this I think no man can go in this track; sensation or feeling is all, and what is left to the cogitative part of our nature, I am not able to comprehend.

I have had occasion to consider each of these paradoxes, excepting that which relates to morals, in “Essays on the Intellectual Powers of Man”; and, though they be strictly connected with each other, and with the system which has produced them, I have attempted to shew that they are inconsistent with just notions of our intellectual powers, no less than they are with the common sense and common language of mankind. And this, I think, will likewise appear with regard to the conclusion relating to morals—to wit, That moral approbation is only an agreeable feeling, and not a real judgment.

To prevent ambiguity as much as possible, let us attend to the meaning of Feeling and of Judgment. These operations of the mind, perhaps, cannot be logically defined; but they are well understood, and easily distinguished, by their properties and adjuncts.

A feeling must be agreeable, or uneasy, or indifferent. It may be weak or strong. It is Edition: current; Page: [190] expressed in language either by a single word, or by such a contexture of words as may be the subject or predicate of a proposition, but such as cannot by themselves make a proposition. For it implies neither affirmation nor negation; and therefore cannot have the qualities of true or false, which distinguish propositions from all other forms of speech, and judgments from all other acts of the mind.

That I have such a feeling, is indeed an affirmative proposition, and expresses testimony grounded upon an intuitive judgment. But the feeling is only one term of this proposition; and it can only make a proposition when joined with another term, by a verb affirming or denying.

As feeling distinguishes the animal nature from the inanimate; so judging seems to distinguish the rational nature from the merely animal.

Though judgment in general is expressed by one word in language, as the most complex operations of the mind may be; yet a particular judgment can only be expressed by a sentence, and by that kind of sentence which logicians call a proposition, in which there must necessarily be a verb in the indicative mood, either expressed or understood.

Every judgment must necessarily be true or false, and the same may be said of the proposition which expresses it. It is a determination of the understanding, with regard to what is true, or false, or dubious.

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In judgment, we can distinguish the object about which we judge, from the act of the mind in judging of that object. In mere feeling there is no such distinction. The object of judgment must be expressed by a proposition; and belief, disbelief, or doubt, always accompanies the judgment we form. If we judge the proposition to be true, we must believe it; if we judge it to be false, we must disbelieve it; and if we be uncertain whether it be true or false, we must doubt.

These two operations of mind, when we consider them separately, are very different, and easily distinguished. When we feel without judging, or judge without feeling, it is impossible, without very gross inattention, to mistake the one for the other.

But in many operations of the mind, both are inseparably conjoined under one name; and when we are not aware that the operation is complex, we may take one ingredient to be the whole, and overlook the other.

But in most of the operations of mind in which judgment or belief is combined with feeling, the feeling is the consequence of the judgment, and is regulated by it.

Let me now consider how I am affected when I see a man exerting himself nobly in a good cause. I am conscious that the effect of his conduct on my mind is complex, though it may be called by one name. I look up to his virtue, I approve, I admire Edition: current; Page: [192] it. In doing so, I have pleasure indeed, or an agreeable feeling; this is granted. But I find myself interested in his success and in his fame. This is affection; it is love and esteem, which is more than mere feeling. The man is the object of this esteem; but in mere feeling there is no object.

I am likewise conscious that this agreeable feeling in me, and this esteem of him, depend entirely upon the judgment I form of his conduct. I judge that this conduct merits esteem; and, while I thus judge, I cannot but esteem him, and contemplate his conduct with pleasure. Persuade me that he was bribed, or that he acted from some mercenary or bad motive, immediately my esteem and my agreeable feeling vanish.

In the approbation of a good action, therefore, there is feeling indeed, but there is also esteem of the agent; and both the feeling and the esteem depend upon the judgment we form of his conduct.

When I exercise my moral faculty about my own actions or those of other men, I am conscious that I judge as well as feel. I accuse and excuse, I acquit and condemn, I assent and dissent, I believe and disbelieve, and doubt. These are acts of judgment, and not feelings.

Suppose that, in a case well known to both, my friend says—Such a man did well and worthily, his conduct is highly approvable. This speech, according Edition: current; Page: [193] to all rules of interpretation, expresses my friend’s judgment of the man’s conduct. This judgment may be true or false, and I may agree in opinion with him, or I may dissent from him without offence, as we may differ in other matters of judgment.

Suppose, again, that, in relation to the same case, my friend says—The man’s conduct gave me a very agreeable feeling.

This speech, if approbation be nothing but an agreeable feeling, must have the very same meaning with the first, and express neither more nor less. But this cannot be, for two reasons.

First, Because there is no rule in grammar or rhetoric, nor any usage in language, by which these two speeches can be construed so as to have the same meaning. The first expresses plainly an opinion or judgment of the conduct of the man, but says nothing of the speaker. The second only testifies a fact concerning the speaker—to wit, that he had such a feeling.

Another reason why these two speeches cannot mean the same thing is, that the first may be contradicted without any ground of offence, such contradiction being only a difference of opinion, which, to a reasonable man, gives no offence. But the second speech cannot be contradicted without an affront: for, as every man must know his own feelings, to deny that a man had a feeling which he affirms he had, is to charge him with falsehood.

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If moral approbation be a real judgment, which produces an agreeable feeling in the mind of him who judges, both speeches are perfectly intelligible, in the most obvious and literal sense. Their meaning is different, but they are related, so that the one may be inferred from the other, as we infer the effect from the cause, or the cause from the effect. I know, that what a man judges to be a very worthy action, he contemplates with pleasure; and what he contemplates with pleasure must, in his judgment, have worth. But the judgment and the feeling are different acts of his mind, though connected as cause and effect. He can express either the one or the other with perfect propriety; but the speech, which expresses his feeling, is altogether improper and inept to express his judgment, for this evident reason, that judgment and feeling, though in some cases connected, are things in their nature different.1

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There is in nature a well-known distinction of things progressive, and stationary, to which we must attend in the farther pursuit of our subject.

To be stationary, it is not necessary that a subject should be incapable of change, even from the action of any external cause; it is sufficient that it have not any principle of change in its own nature. To be progressive, on the contrary, does not consist in any variation or change which an external cause may produce; but in those transitions, from one state to another, which proceed from a principle of advancement in the subject itself.

A block of stone, from the quarry, may receive, in the hands of a workman, any variety of forms, but left to itself, would remain in its state.

A seedling plant on the contrary, in a favourable soil and exposure, takes root and grows of itself.

Progressive natures are subject to vicissitudes of advancement or decline, but are not stationary, perhaps, in any period of their existence. Thus, in Edition: current; Page: [198] the material world, subjects organized being progressive, when they cease to advance, begin to decline, however insensibly, at the time of their transition from one to the other. In this consist the operation or failure of vegetable and animal life. In their advancement, the matter of which they are composed accumulates, and at every period acquires a form that approaches to the end of their progress. The principle of life itself gains strength or ability to discharge, and to vary, the functions of nature. In their decline they fade, shrink, and abate of their vigour and force.

Intelligence appears to be, in a still higher degree, a principle of progression, and subject to greater extremes of comparative advancement or degradation. It is advanced by continual accessions of observation and knowledge; of skill and habit, in the practice of arts; of improving discernment of good and evil; of resolute purpose or power. It declines through defect of memory, discernment, affection, and resolution.

While subjects stationary are described by the enumeration of co-existent parts, and quiescent qualities, subjects progressive are characterized by the enumeration of steps, in the passage from one form or state of existence to another, and by the termination or point of approach, whether near or remote, to which the successive movements of their nature are directed.

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The rank of a progressive subject is to be estimated, not by its condition at any particular stage of its progress, but by its capacity and destination to advance in the scale of being. From the feeblest shoot or seed-leaf of the oak, though more diminutive than many plants of the garden, we already forecast the stately fabric it is designed to raise in the forest. In the human infant, though inferior to the young of many other animals, we anticipate the beauty of youth, the vigorous soul of manhood, and the wisdom of age. And the highest rank, in the scale of created existence, is due to that nature, if such there be, which is destined to grow in perfection, and may grow without end: its good is advancement, and its evil, decline.

We are inclined to consider progression as made up of stationary periods; as we consider a circle as a polygon of an infinite number of sides; a fluid as made up of solid parts indefinitely small; and duration itself, as made up of successive points, or indivisible moments of time.

In this our conception is inaccurate, and our reasoning, of course, likely to become incorrect. Progression may, no doubt, be divided into periods; but in no period, perhaps, is the subject stationary. Every subdivision, like the whole of its progress, is a transition from one state to another, and through states intermediate, more or less numerous according to the divisions under which we are pleased to Edition: current; Page: [200] conceive them. The progress of intelligent being, for instance, may be more or less rapid, but is continual; and in the very continuance of existence, and the repetition of consciousness and perception, must receive continual increments of knowledge and thought. Or in the failure of the source from which it derives improvement, it is likely to incur degradation and decline.

For our purpose, however, it is sufficient to observe, that the state of nature or the distinctive character of any progressive being is to be taken, not from its description at the outset, or at any subsequent stage of its progress; but from an accumulative view of its movement throughout. The oak is distinguishable from the pine, not merely by its seed leaf; but by every successive aspect of its form; by its foliage in every successive season; by its acorn; by its spreading top; by its lofty growth, and the length of its period. And the state of nature, relative to every tree in the wood, includes all the varieties of form or dimension through which it is known to pass in the course of its nature.

By parity of reason, the natural state of a living creature includes all its known variations, from the embryo and the fœtus to the breathing animal, the adolescent and the adult, through which life in all its varieties is known to pass.

The state of nature, relative to man, is also a state of progression equally real, and of greater Edition: current; Page: [201] extent. The individual receives the first stamina of his frame in a growing state. His stature is waxing, his limbs and his organs gain strength, and he himself a growing facility in the use of them. His faculties improve by exercise, and are in a continual state of exertion.

If his thoughts pass from one subject to another, he can return to the subject he has left, with some acquired advantage of discernment or comprehension. He accumulates perceptions and observations, takes cognizance of new subjects, without forgetting the old; knows more, of course, at every subsequent period than he did in a former; reasons more securely; penetrates obscurities, which at first embarrassed him; and performs every operation of thought with more facility and more success.

With respect to the period of his existence he sees it but in part. When he looks back to the point from which he set out, he cannot descry it; when he looks forward to the end of his line, he cannot foresee it. He may observe the birth and the death of a fellow creature, but knows nothing of his own. If he were to assume the earliest date he remembers as the beginning of his existence, he might soon be convinced that he overlooked a considerable period which had preceded; or if he should suppose his being to end with the dissolution of his animal frame, it is possible he might be equally mistaken. Yet he finds nothing in the world around him Edition: current; Page: [202] beyond the limits of what he can collect from the remembrance of the past, or infer by sagacity from the laws of nature in foresight of the future, from which he can fix any certain marks of his own beginning or his end.

Such, without entering into the peculiarities or unequal degrees of power incident to different men, we may assume as the state of nature relative to the individual.

The state of nature relative to the species is differently constituted, and of different extent. It consists in the continual succession of one generation to another; in progressive attainments made by different ages; communicated with additions from age to age; and in periods, the farthest advanced, not appearing to have arrived at any necessary limit. This progress indeed is subject to interruption, and may come to a close, or give way to vicissitude at any of its stages; but not more necessarily at the period of highest attainment than at any other.

So long as the son continues to be taught what the father knew, or the pupil begins where the tutor has ended, and is equally bent on advancement; to every generation the state of arts and accommodations already in use serves but as groundwork for new invention and successive improvement. As Newton did not acquiesce in what was observed by Kepler and Galileo; no more have successive astronomers Edition: current; Page: [203] restricted their view to what Newton has demonstrated. And, with respect to the mechanic and commercial arts, even in the midst of the most laboured accommodations, so long as there is any room for improvement, invention is busy as if nothing had yet been done to supply the necessities, or complete the conveniences of human life. But even here, and in all its steps of progression, this active nature, in respect to the advantages, whether of knowledge or art, derived from others, if there be not a certain effort to advance, is exposed to reverse and decline. The generation, in which there is no desire to know more or practise better than its predecessors, will probably neither know so much nor practise so well. And the decline of successive generations, under this wane of intellectual ability, is not less certain than the progress made under the operation of a more active and forward disposition.

Such is the state of nature relative to the human species; and, in this, as in every other progressive subject, the present being intermediate to the past and the future, may be different from either. Each is a part of the whole; and neither can, with any reason, be said to be more natural than the others. It cannot be said, that it is more natural for the oak to spring from its seed than to overshadow the plain; that it is more natural for water to gush from the land in springs than to flow in rivers, and to mix with the sea.

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The state of nature relative to man, however, is sometimes a mere term of abstraction, in which he is stated apart from the society he forms, from the art he invents, the science he acquires, or the political establishment he makes. And, when his progress in any of these respects is to be considered, it is no doubt convenient to consider the particular in question apart from himself, and from every thing else. It is not, however, to be supposed, that man ever existed apart from the qualities and operations of his own nature, or that any one operation and quality existed without the others. The whole, indeed, is connected together, and any part may vary in measure or degree, while in its nature and kind it is still the same.

The child may be considered apart from his parent, and the parent apart from his child; but the latter would not have existed without the former. If we trace human society back to this its simplest constitution, even there the society was real. If we trace human thought back to its simplest exertions, even there it was an exercise of understanding, and some effort of invention or skill.

The groups in which the rudest of men were placed, had their chiefs and their members; and nothing that the human species ever attained, in the latest period of its progress, was altogether without a germ or principle from which it is derived, in the earliest or most ancient state of mankind.

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It may no doubt be convenient, we may again repeat, in speculation, or in assigning the origin and in deriving the progress of any attainment, to consider the attainment itself abstractly, or apart from the faculty or power by which it is made; and we must not deny ourselves the use of such abstractions, in treating of human nature, any more than in treating of any other subject. But there is a caution to be observed in the use of abstractions, relating to any subject whatever: That they be not mistaken for realities, nor obtruded for historical facts.

The language of geometry is necessarily abstract. A point is mere place, considered apart from any dimension whatever. A line is length, considered apart from breadth or thickness. A surface is length and breadth, considered apart from thickness. And, in a solid, all the dimensions of length, breadth, and thickness, are admitted. But the geometrical abstractions are nowhere mistaken for realities: length is not supposed to exist without breadth, nor length and breadth without thickness. Or, if such mistakes are actually made, yet, no one would infer that lines are more natural than surfaces, or surfaces more natural than solids.

Such mistake and misapprehension of terms is scarcely admitted, except in treating of human nature. In every other progressive subject, progression Edition: current; Page: [206] itself, not any particular step in the progress, is supposed to constitute the natural state. The last shoot of the oak, after it has stood five hundred years in the forest, and carried a thousand branches, is not deemed less natural than the first.

Under this term, of the State of Nature, authors affect to look back to the first ages of man, not without some apparent design to depreciate his nature, by placing his origin in some unfavourable point of view; as we derogate, from the supposed honours of a family, by looking back to the mechanics or peasants, from whom its ancestors were descended.

Hobbes contended, that men were originally in a state of war, and undisposed to amity or peace; that society, altogether unnatural to its members, is to be established and preserved by force. Or this, at least, may be supposed to follow from his general assumption that the state of nature was a state of war.

If this point must be seriously argued, we may ask in what sense war is the state of nature? Not surely the only state of which men are susceptible; for we find them at peace as well as at war: nor can we suppose it the state which mankind ought at all times to prefer; for it labours under many inconveniences and defects. But it was, we may be told, the first and the earliest state, from which men were relieved by convention and adventitious establishments.

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This assertion, that war was the earliest state of mankind, is made without proof; for the first ages of the human species, in times past, are as little known as the last, that may close the scene of its being in times to come. In every progression, it is true, may be conceived a point of origin, and a point of termination, to be collected from the direction in which the progress proceeds. The sun, even by a person who never saw him rise or set, may be supposed, from the course he holds, to have risen in the east, and to set in the west. Man, who is advancing in knowledge and art, may be supposed to have begun in ignorance or rudeness; but it is not necessary to suppose that a species, of whom the individuals are sometimes at war, and sometimes at peace, must have begun in war. There is, on the contrary, much reason to suppose, that they began in peace, and continued in peace, until some occasion of quarrel arose between them.

The progress of the species, in population and numbers, implies an original peace, at least, between the sexes, and between the parent and his child, in family together; and, if we are to suppose a state of war between brothers, this, at least, must have been posterior to the peace in which they were born and brought up, to the peace in which they arrived at the possession of those talents, and that force, which they come to employ for mutual destruction.

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Another philosopher, in this school of nature, has chosen to fix the original description of man, in a state of brutality, unconscious of himself, and ignorant of his kind; so far from being destined to the use of reason, that all the attempts he has made at the exercise of this dangerous faculty have opened but one continual source of depravation and misery.

But, as the former of these philosophers has not told us what beneficent power, different from man himself, has made peace for this refractory being; no more has the other informed us, who invented reason for man; whose thoughts and reflections first disturbed the tranquillity of his brutal nature, and brought this victim of care into this anxious state of reflection, to which are imputed so many of his follies and sufferings.

Until we are told by whom the state of nature was done away, and a new one substituted, we must continue to suppose that this is the work of man himself; and the whole of what these shrewd philosophers have taught, amounts to no more than this, that man would be found in a state of war, or in a state of brutality, if it were not for himself, for his own qualifications and his endeavours to obtain a better; and that, in reality, the situation he gains is the effect of a faculty by which he is disposed to choose for himself.

This we are ready to admit. Man is made for Edition: current; Page: [209] society and the attainments of reason. If, by any conjuncture, he is deprived of these advantages, he will sooner or later find his way to them. If he came from a beginning, defective in these respects, he was, from the first, disposed to supply his defects; in process of time has actually done so; continued to improve upon every advantage he gains; and thus to advance, we may again repeat, is the state of nature relative to him.

It were absurd to think of depreciating a progressive being, by pointing out the state of defect, from which he has passed, to the attainment of a better and a higher condition; for so to pass is the specific excellence of his nature.

The grandeur of the forest is not the less real, for its having sprung up from among the weeds of the field: the genius of Newton not the less to be admired, for his having grown up from the ignorance and simplicity of his infant years: nor the policy of Athens, Sparta, or Rome, less to be valued, because they may have sprung from hordes, no way superior to those who are now found in different parts of Africa or America.

It is the nature of progression to have an origin, far short of the attainments which it is directed to make; and not any precise measure of attainment, but the passage or transition from defect to perfection is that which constitutes the felicity of a progressive nature. The happy being, accordingly, Edition: current; Page: [210] whose destination is to better himself, must not consider the defect under which he labours, at the outset, or in any subsequent part of his progress, as a limit set to his ambition, but as an occasion and a spur to his efforts.

The life and activity of intelligent beings consists in the consciousness or perception of an improveable state, and in the effort to operate upon it for the better. This constitutes an unremitting principle of ambition in human nature. Men have different objects, and succeed unequally in the pursuit of them: but every person, in one sense or another, is earnest to better himself.

Man is by nature an artist, endowed with ingenuity, discernment, and will. These faculties he is qualified to employ on different materials; but is chiefly concerned to employ them on himself: over this subject his power is most immediate and most complete; as he may know the law, according to which his progress is effected, by conforming himself to it, he may hasten or secure the result.

The bulk of mankind are, like other parts of the system, subjected to the law of their nature, and, without knowing it, are led to accomplish its purpose: while they intend no more than subsistence and accommodation or the peace of society, and the safety of their persons and their property, their faculties are brought into use, and they profit by Edition: current; Page: [211] exercise. In mutually conducting their relative interests and concerns, they acquire the habits of political life; are made to taste of their highest enjoyments, in the affections of benevolence, integrity, and elevation of mind; and, before they have deliberately considered in what the merit or felicity of their own nature consist, have already learned to perform many of its noblest functions.

Nature in this as in many other instances does not entrust the conduct of her works to the precarious views and designs of any subordinate agent. But if the progress of man in every instance were matter of necessity or even of contingency, and no way dependent on his will, nor subjected to his command, we should conclude that this sovereign rank and responsibility of a moral agent with which he is vested were given in vain; and the capacity of erecting a fabric of art, on the foundation of the laws of nature, were denied to him in that department precisely in which they are of the highest account. If he may work on the clay that is placed under his foot, and form it into models of grace and beauty; if he may employ the powers of gravitation, elasticity, and magnetism, as the ministers of his pleasure; we may suppose, also, that the knowledge of laws operating on himself should direct him how to proceed, and enable him to hasten the advantages, to which his progressive Edition: current; Page: [212] nature is competent. If his Maker have destined his faculties to improve by exercise, and by the attainment of habits, there is no doubt that he himself may choose what exercise he will perform, and what habits he shall acquire.

But in order to profit by the laws of progression which take place in his frame, it behoves him to recollect what they are, and to take his resolution respecting the purpose to which he will apply their force.

To this object, he is urged at once by the double consideration of a good to be obtained, and of an evil to be avoided. Most subjects in nature, which, from the energy of a salutary principle, are susceptible of advancement, are likewise, by the failure or abuse of that principle, susceptible of degradation and ruin. Plants and animals are known to perish, in the same gradual manner in which they advance into strength and beauty. Man, with whom the sources of good and of evil are more entrusted to his own management, is likewise exposed, in a much higher degree, to the extremes of comparative degradation and misery. The progress of nations in one age to high measures of intellectual attainment and cultivated manners is not more remarkable than the decline that sometimes ensues in their fall to extreme depravation and intellectual debility.

It may not be in the power of the individual Edition: current; Page: [213] greatly to promote the advancement or to retard the decline of his country. But every person, being principally interested in himself, is the absolute master of his own will, and for the choice he shall have made is alone responsible.1

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On hearing these propositions,—I exist, things equal to one and the same thing are equal to one another, the sun rose to-day, there is a God, ingratitude ought to be blamed and punished, the three angles of a triangle are equal to two right angles, etc.—I am conscious that my mind admits and acquiesces in them. I say, that I believe them to be true; that is, I conceive them to express something conformable to the nature of things. Of the contrary propositions I should say, that my mind does not acquiesce in them, but disbelieves them, and conceives them to express something not conformable to the nature of things. My judgment in this case, I conceive to be the same that I should form in regard to these propositions, if I were perfectly acquainted with all nature, in all its parts, and in all its laws.

If I be asked, what I mean by the nature of things, I cannot otherwise explain myself than by saying, that there is in my mind something which induces Edition: current; Page: [218] me to think, that every thing existing in nature is determined to exist, and to exist after a certain manner, in consequence of established laws; and that whatever is agreeable to those laws is agreeable to the nature of things, because by those laws the nature of all things is determined. Of those laws I do not pretend to know any thing except so far as they seem to be intimated to me by my own feelings, and by the suggestions of my own understanding. But these feelings and suggestions are such, and affect me in such a manner, that I cannot help receiving them, and trusting in them, and believing that their intimations are not fallacious, but such as I should approve if I were perfectly acquainted with every thing in the universe, and such as I may approve, and admit of, and regulate my conduct by, without danger of any inconvenience.

It is not easy on this subject to avoid identical expressions. I am not certain that I have been able to avoid them. And perhaps I might have expressed my meaning more shortly and more clearly, by saying, that I account that to be truth which the constitution of our nature determines us to believe, and that to be falsehood which the constitution of our nature determines us to disbelieve. Believing and disbelieving are simple acts of the mind; I can neither define nor describe them in words; and therefore the reader must judge of their nature Edition: current; Page: [219] from his own experience. We often believe what we afterwards find to be false; but while belief continues, we think it true; when we discover its falsity, we believe it no longer.

Hitherto I have used the word belief to denote an act of the mind which attends the perception of truth in general. But truths are of different kinds; some are certain, others only probable: and we ought not to call that act of the mind which attends the perception of certainty, and that which attends the perception of probability, by one and the same name. Some have called the former conviction, and the latter assent. All convictions are equally strong; but assent admits of innumerable degrees, from moral certainty, which is the highest degree, downward, through the several stages of opinion, to that suspense of judgment which is called doubt.

We may, without absurdity, speak of probable truth, as well as of certain truth. Whatever a rational being is determined, by the constitution of his nature, to admit as probable, may be called probable truth; the acknowledgment of it is as universal as that rational nature, and will be as permanent. But, in this enquiry, we propose to confine ourselves chiefly to that kind of truth which may be called certain, which enforces our conviction, and the belief of which, in a sound mind, is not tinctured with any doubt or uncertainty.

The investigation and perception of truth is Edition: current; Page: [220] commonly ascribed to our rational faculties; and these have by some been reduced to two,—Reason and Judgment; the former being supposed to be conversant about certain truths, the latter chiefly about probabilities. But certain truths are not all of the same kind; some being supported by one sort of evidence and others by another: different energies of the understanding must therefore be exerted in perceiving them; and these different energies must be expressed by different names, if we would speak of them distinctly and intelligibly. The certainty of some truths, for instance, is perceived intuitively; the certainty of others is perceived not intuitively, but in consequence of a proof. Most of the propositions of Euclid are of the latter kind; the axioms of geometry are of the former. Now, if that faculty by which we perceive truth in consequence of a proof, be called Reason, that power by which we perceive self-evident truth ought to be distinguished by a different name. It is of little consequence what name we make choice of, provided that in choosing it we depart not from the analogy of language; and that, in applying it, we avoid equivocation and ambiguity. Some philosophers of note have given the name of Common Sense to that faculty by which we perceive self-evident truth; and, as the term seems proper enough, we shall adopt it.1

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The term Common Sense has several different significations. 1. Sometimes it seems to be synonymous with prudence. Thus we say, that a man has a large stock of common sense, who is quick in perceiving remote consequences, and thence instantaneously determines concerning the propriety of present conduct. 2. We often meet with persons of great sagacity in most of the ordinary affairs of life, and very capable of accurate reasoning, who yet, without any bad intention, commit blunders in regard to decorum; by saying or doing what is offensive to their company, and inconsistent with their own character; and this we are apt to impute to a defect in common sense. But it seems rather to be owing to a defect in that kind of sensibility, or sympathy, by which we suppose ourselves in the situations of others, adopt their sentiments, and in a manner perceive their thoughts; and which is indeed the foundation of good breeding. It is by this secret, and sudden, and (to those who are unacquainted with it) inexplicable communication of feelings, that a man is enabled to avoid what would appear incongruous or offensive. They who are prompted by inclination, or obliged by necessity, to study the art of recommending themselves to others, acquire a wonderful facility in perceiving and avoiding all possible ways of giving offence; which is a proof, that this kind of sensibility may be improved by habit; although Edition: current; Page: [222] there are, no doubt, in respect of this, as well as of some other modifications of perception, original and constitutional differences in the frame of different minds. 3. Some men are distinguished by an uncommon acuteness in discovering the characters of others; they seem to read the soul in the countenance, and with a single glance to penetrate the deepest recesses of the heart. In their presence, the hypocrite is detected, notwithstanding his specious outside; the gay effrontery of the coxcomb cannot conceal his insignificance; and the man of merit appears conspicuous under all the disguises of an ungainly modesty. This talent is sometimes called Common Sense; but improperly. It is far from being common; it is even exceedingly rare: it is to be found in men who are not remarkable for any other mental excellence; and we often see those who in other respects are judicious enough, quite destitute of it. 4. Neither ought every common opinion to be referred to common sense. Modes in dress, religion, and conversation, however absurd in themselves, may suit the notions or the taste of a particular people: but none of us will say, that it is agreeable to common sense, to worship more gods than one; to believe that one and the same body may be in ten thousand different places at the same time; to like a face the better because it is painted, or to dislike a person because he does not lisp in his pronunciation. Lastly, the Edition: current; Page: [223] term Common Sense has been used by some philosophers to signify that power of the mind which perceives truth, or commands belief, not by progressive argumentation, but by an instantaneous and instinctive impulse; derived neither from education nor from habit, but from nature; acting independently on our will, whenever its object is presented, according to an established law, and therefore not improperly called Sense; and acting in a similar manner upon all mankind, and therefore properly called Common Sense. It is in this signification that the term Common Sense is used in the present enquiry.

That there is a real and essential difference between these two faculties; that common sense cannot be accounted for, by being called the perfection of reason, nor reason, by being resolved into common sense, will perhaps appear from the following remarks. 1. We are conscious, from internal feeling, that the energy of understanding which perceives intuitive truth, is different from that other energy which unites a conclusion with a first principle, by a gradual chain of intermediate relations. We believe the truth of an investigated conclusion, because we can assign a reason for our belief; we believe an intuitive principle, without being able to assign any other reason but this, that we know it to be true; or that the law of our nature, or the constitution of the human understanding, Edition: current; Page: [224] determines us to believe it. 2. We cannot discern any necessary connection between reason and common sense: they are indeed generally connected; but we can conceive a being endued with the one who is destitute of the other. Nay, we often find, that this is in fact the case. In dreams, we sometimes reason without common sense. Through a defect of common sense, we adopt absurd principles; but supposing our principles true, our reasoning is often unexceptionable.1

In the science of body, glorious discoveries have been made by a right use of reason. When men are once satisfied to take things as they find them; when they believe Nature upon her bare declaration, without suspecting her of any design to impose upon them; when their utmost ambition is to be her servants and interpreters; then, and not till then, will philosophy prosper. But of those who have applied themselves to the science of human nature, it may truly be said, (of many of them at least), that too much reasoning hath made them mad. Nature speaks to us by our external, as well as by our internal, senses; it is strange that we should believe her in the one case, and not in the other; it is most strange, that supposing her fallacious, we should think ourselves capable of detecting the cheat. Common sense tells me, that the ground on which I stand is hard, material, and Edition: current; Page: [225] solid, and has a real, separate, independent existence. Berkeley and Hume tell me, that I am imposed upon in this matter; for that the ground under my feet is really an idea in my mind; that its very essence consists in being perceived; and that the same instant it ceases to be perceived, it must also cease to exist; in a word, that to be, and to be perceived, when predicated of the ground, the sun, the starry heavens, or any corporeal object, signify precisely the same thing. Now, if my common sense be mistaken, who shall ascertain and correct the mistake? Our reason, it is said. Are then the inferences of reason in this instance clearer, and more decisive, than the dictates of common sense? By no means: I still trust to my common sense as before; and I feel that I must do so. But supposing the inferences of the one faculty as clear and decisive as the dictates of the other; yet who will assure me, that my reason is less liable to mistake than my common sense? And if reason be mistaken, what shall we say? Is this mistake to be rectified by a second reasoning, as liable to mistake as the first?—In a word, we must deny the distinction between truth and falsehood, adopt universal scepticism, and wander without end from one maze of uncertainty to another; a state of mind so miserable, that Milton makes it one of the torments of the damned;—or else we must suppose, that one of these faculties is of higher authority Edition: current; Page: [226] than the other; and that either reason ought to submit to common sense, or common sense to reason, whenever a variance happens between them:—in other words, that no doctrine ought to be admitted as true that exceeds belief, and contradicts a first principle.

It has been said, that every enquiry in philosophy ought to begin with doubt;—that nothing is to be taken for granted, and nothing believed, without proof. If this be admitted, it must also be admitted, that reason is the ultimate judge of truth, to which common sense must continually act in subordination. But this I cannot admit; because I am able to prove the contrary by incontestable evidence. I am able to prove, that “except we believe many things without proof, we never can believe any thing at all; for that all sound reasoning must ultimately rest on the principles of common sense; that is, on principles intuitively certain or intuitively probable; and consequently, that common sense is the ultimate judge of truth, to which reason must continually act in subordination.”—This I mean to prove by a fair induction of particulars.1

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1. All the different kinds of philosophical inquiry, and all that practical knowledge which guides our conduct in life, presuppose such an established order in the succession of events, as enables us to form conjectures concerning the future, from the observation of the past.

2. In the phenomena of the material world, and in many of the phenomena of mind, more especially in those which depend on the instincts of the brutes, we expect, with the most perfect confidence, that in the same combinations of circumstances the same results will take place; and it is owing to this expectation (justified by the experience of all ages) that the instincts of the brutes, as well as the laws of matter, become a source of power to man. In both cases, the established order of nature affords abundant evidence that it was chiefly with a view to our accommodation and happiness that the arrangements of this world were made. The laws Edition: current; Page: [230] which regulate the course of human affairs, are investigated with much greater difficulty: but, even in this class of events, such a degree of order may frequently be traced, as furnishes general rules of great practical utility; and this order becomes the more apparent, in proportion as we generalize our observations.

3. Our knowledge of the laws of nature is entirely the result of observation and experiment; for there is no instance in which we perceive such a necessary connexion between two successive events, as might enable us to infer the one from the other by reasoning a priori. We find, from experience, that certain events are invariably conjoined, so that when we see the one, we expect the other; but our knowledge in such cases extends no farther than the fact.

4. To ascertain those established conjunctions of successive events, which constitute the order of the universe;—to record the phenomena which it exhibits to our observation, and to refer them to their general laws, is the great business of philosophy. Lord Bacon was the first person who was fully aware of the importance of this fundamental truth. The ancients considered philosophy as the science of causes; and hence were led to many speculations, to which the human faculties are altogether incompetent.

5. The ultimate object of philosophical inquiry Edition: current; Page: [231] is the same which every man of plain understanding proposes to himself, when he remarks the events which fall under his observation, with a view to the future regulation of his conduct. The more knowledge of this kind we acquire, the better can we accommodate our plans to the established order of things, and avail ourselves of natural Powers and Agents for accomplishing our purposes.

6. The knowledge of the Philosopher differs from that sagacity which directs uneducated men in the business of life, not in kind, but in degree, and in the manner in which it is acquired. 1st, By artificial combinations of circumstances, or, in other words, by experiments, he discovers many natural conjunctions which would not have occurred spontaneously to his observation. 2dly, By investigating the general Laws of Nature, and by reasoning from them synthetically, he can often trace an established order, where a mere observer of facts would perceive nothing but irregularity. This last process of the mind is more peculiarly dignified with the name of Philosophy; and the object of the rules of philosophizing is to explain in what manner it ought to be conducted.

7. The knowledge which is acquired of the course of Nature by mere observation, is extremely limited, and extends only to cases in which the uniformity of the observed phenomena is apparent to our senses. This happens, either when one single Edition: current; Page: [232] law of nature operates separately, or when different laws are always combined together in the same manner. In most instances, however, when different laws are combined, the result varies in every particular case, according to the different circumstances of the combination; and it is only by knowing what the laws are which are concerned in any expected phenomenon, and by considering in what manner they modify each other’s effects, that the result can be predicted.

8. Hence it follows, that the first step in the study of Philosophy is to ascertain the simple and general laws on which the complicated phenomena of the universe depend. Having obtained these laws, we may proceed safely to reason concerning the effect resulting from any given combination of them. In the former instance, we are said to carry on our inquiries in the way of Analysis; in the latter in that of Synthesis.—[Scala Ascensoria et Descensoria.—Bacon.]

9. To this method of philosophizing, (which is commonly distinguished by the title of the Method of Induction), we are indebted for the rapid progress which physical knowledge has made since the time of Lord Bacon. The publication of his writings fixes one of the most important eras in the history of science. Not that the reformation which has since taken place in the plan of philosophical inquiry is to be ascribed entirely to him; for Edition: current; Page: [233] although he did more to forward it than any other individual, yet his genius and writings seem to have been powerfully influenced by the circumstances and character of the age in which he lived; and there can be little doubt that he only accelerated an event which was already prepared by many concurrent causes.1


The effect of custom in connecting together different thoughts, in such a manner that the one seems spontaneously to follow the other, is one of the most obvious facts with respect to the operations of the mind. To this law of our constitution, modern philosophers have given the name of the Association of Ideas. Of late, the phrase has been used in a more extensive sense, to denote the tendency which our thoughts have to succeed each other in a regular train; whether the connexion between them be established by custom, or arise from some other associating principle.

What the different circumstances are which regulate the succession of our thoughts, it is not possible, perhaps, to enumerate completely. The following are some of the most remarkable: Resemblance, Analogy, Contrariety, Vicinity in Place, Vicinity in Time, Relation of Cause and Effect, Relation of Means and End, Relation of Premises Edition: current; Page: [234] and Conclusion. Whether some of these may not be resolvable into others, is not very material to inquire. The most powerful of all the associating principles is undoubtedly Custom; and it is that which leads to the most important inquiries of a practical nature.

Among the associating principles already enumerated, there is an important distinction. The relations on which some of them are founded are obvious; and connect our thoughts together, when the attention is not directed particularly to any subject. Other relations are discovered only in consequence of efforts of meditation or study. Of the former kind are the relations of Resemblance and Analogy, of Contrariety, of Vicinity in Time and Place; of the latter, the Relations of Cause and Effect, of Means and End, of Premises and Conclusion. It is owing to this distinction that transitions, which would be highly offensive in philosophical writing, are the most pleasing of any in poetry.

In so far as the train of our thoughts is regulated by the laws of Association, it depends on causes of the nature of which we are ignorant, and over which we have no direct or immediate control. At the same time it is evident, that the will has some influence over this part of our constitution. To ascertain the extent and the limits of this influence, is a problem of equal curiosity and importance.

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We have not a power of summoning up any particular thought, till that thought first solicit our notice. Among a crowd, however, which present themselves, we can choose and reject. We can detail a particular thought, and thus check the train that would otherwise have taken place.

The indirect influence of the will over the train of our thoughts is very extensive. It is exerted chiefly in two ways:—1. By an effort of attention, we can check the spontaneous course of our ideas, and give efficacy to those associating principles which prevail in a studious and collected mind. 2. By practice, we can strengthen a particular associating principle to so great a degree, as to acquire a command over a particular class of our ideas.

The effect of habit, in subjecting to the will those intellectual processes, which are the foundation of wit,—of the mechanical part of poetry, (or, in other words, of the powers of versification and rhyming),—of poetical fancy,—of invention in the arts and sciences; and, above all, its effect in forming a talent for extempore elocution, furnish striking illustrations of this last remark.

Of all the different parts of our constitution, there is none more interesting to the student of Moral Philosophy than the laws which regulate the Association of Ideas. From the intimate and almost indissoluble combinations which we are thus led to form in infancy and in early youth, may be Edition: current; Page: [236] traced many of our speculative errors; many of our most powerful principles of action; many perversions of our moral judgment; and many of those prejudices which mislead us in the conduct of life. By means of a judicious education, this susceptibility of the infant mind might be rendered subservient not only to moral improvement, but to the enlargement and multiplication of our capacities of enjoyment.1


By means of the Association of Ideas, a constant current of thoughts, if I may use the expression, is made to pass through the mind while we are awake. Sometimes the current is interrupted, and the thoughts diverted into a new channel, in consequence of the ideas suggested by other men, or of the objects of perception with which we are surrounded. So completely, however, is the mind in this particular subjected to physical laws, that it has been justly observed,2 we cannot by an effort of our will call up any one thought, and that the train of our ideas depends on causes which operate in a manner inexplicable by us.

This observation, although it has been censured as paradoxical, is almost self-evident; for, to call up a particular thought supposes it to be already Edition: current; Page: [237] in the mind. As I shall have frequent occasion, however, to refer to the observation afterwards, I shall endeavour to obviate the only objection which I think can reasonably be urged against it, and which is founded on that operation of the mind which is commonly called recollection or intentional memory.

It is evident, that before we attempt to recollect the particular circumstances of any event, that event in general must have been an object of our attention. We remember the outlines of the story, but cannot at first give a complete account of it. If we wish to recall these circumstances, there are only two ways in which we can proceed. We must either form different suppositions, and then consider which of these tallies best with the other circumstances of the event; or, by revolving in our mind the circumstances we remember, we must endeavour to excite the recollection of the other circumstances associated with them. The first of these processes is, properly speaking, an inference of reason, and plainly furnishes no exception to the doctrine already delivered. We have an instance of the other mode of recollection, when we are at a loss for the beginning of a sentence in reciting a composition that we do not perfectly remember, in which case we naturally repeat over, two or three times, the concluding words of the preceding sentence, in order to call up the other Edition: current; Page: [238] words which used to be connected with them in the memory. In this instance, it is evident that the circumstances we desire to remember are not recalled to the mind in immediate consequence of an exertion of volition, but are suggested by some other circumstances with which they are connected, independently of our will, by the laws of our constitution.

Notwithstanding, however, the immediate dependence of the train of our thoughts on the laws of association, it must not be imagined that the will possesses no influence over it. This influence, indeed, is not exercised directly and immediately, as we are apt to suppose on a superficial view of the subject; but it is, nevertheless, very extensive in its effects, and the different degrees in which it is possessed by different individuals, constitute some of the most striking inequalities among men, in point of intellectual capacity.

Of the powers which the mind possesses over the train of its thoughts, the most obvious is its power of singling out any one of them at pleasure, of detaining it, and of making it a particular object of attention. By doing so, we not only stop the succession that would otherwise take place, but in consequence of our bringing to view the less obvious relations among our ideas, we frequently divert the current of our thoughts into a new channel. If, for example, when I am indolent and inactive, the Edition: current; Page: [239] name of Sir Isaac Newton accidentally occur to me, it will perhaps suggest one after another the names of some other eminent mathematicians and astronomers, or of some of his illustrious contemporaries and friends, and a number of them may pass in review before me, without engaging my curiosity in any considerable degree. In a different state of mind, the name of Newton will lead my thoughts to the principal incidents of his life, and the more striking features of his character; or, if my mind be ardent and vigorous, will lead my attention to the sublime discoveries he made, and gradually engage me in some philosophical investigation. To every object, there are others which bear obvious and striking relations; and others, also, whose relation to it does not readily occur to us, unless we dwell upon it for some time, and place it before us in different points of view.

But the principal power we possess over the train of our ideas, is founded on the influence which our habits of thinking have on the laws of Association; an influence which is so great, that we may often form a pretty shrewd judgment concerning a man’s prevailing turn of thought, from the transitions he makes in conversation or in writing. It is well known, too, that by means of habit, a particular associating principle may be strengthened to such a degree, as to give us a command of all the different ideas in our mind which have a certain Edition: current; Page: [240] relation to each other, so that when any one of the class occurs to us, we have almost a certainty that it will suggest the rest. What confidence in his own powers must a speaker possess, when he rises without premeditation in a popular assembly, to amuse his audience with a lively or a humorous speech! Such a confidence, it is evident, can only arise from a long experience of the strength of particular associating principles.

To how great a degree this part of our constitution may be influenced by habit, appears from facts which are familiar to every one. A man who has an ambition to become a punster, seldom or never fails in the attainment of his object; that is, he seldom or never fails in acquiring a power which other men have not, of summoning up on a particular occasion a number of words different from each other in meaning, and resembling each other more or less in sound. I am inclined to think that even genuine wit is a habit acquired in a similar way; and that, although some individuals may from natural constitution be more fitted than others to acquire this habit, it is founded in every case on a peculiarly strong association among certain classes of our ideas, which gives the person who possesses it a command over those ideas which is denied to ordinary men. But there is no instance in which the effect of habits of association is more remarkable than in those men who possess a facility of rhyming. That Edition: current; Page: [241] a man should be able to express his thoughts perspicuously and elegantly, under the restraints which rhyme imposes, would appear to be incredible if we did not know it to be fact. Such a power implies a wonderful command both of ideas and of expression, and yet daily experience shews that it may be gained with very little practice. Pope tells us with respect to himself, that he could express himself not only more concisely but more easily in rhyme than in prose.

Nor is it only in these trifling accomplishments that we may trace the influence of habits of association. In every instance of invention, either in the fine arts, in the mechanical arts, or in the sciences, there is some new idea, or some new combination of ideas, brought to light by the inventor. This, undoubtedly, may often happen in a way which he is unable to explain; that is, his invention may be suggested to him by some lucky thought, the origin of which he is unable to trace. But when a man possesses a habitual fertility of invention in any particular art or science, and can rely, with confidence, on his inventive powers, whenever he is called upon to exert them, he must have acquired, by previous habits of study, a command over certain classes of his ideas, which enables him at pleasure to bring them under his review.1

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In order to illustrate a little farther the influence of the Association of Ideas on the human mind, I shall add a few remarks on some of its effects on our active and moral principles. In stating these remarks, I shall endeavour to avoid, as much as possible, every occasion of controversy, by confining myself to such general views of the subject, as do not presuppose any particular enumeration of our original principles of action, or any particular system concerning the nature of the moral faculty. If my health and leisure enable me to carry my plans into execution, I propose, in the sequel of this work, to resume these inquiries, and to examine the various opinions to which they have given rise.

The manner in which the association of ideas operates in producing new principles of action, has been explained very distinctly by different writers. Whatever conduces to the gratification of any natural appetite, or of any natural desire, is itself desired on account of the end to which it is subservient; and by being thus habitually associated in our apprehension with agreeable objects, it frequently comes, in process of time, to be regarded as valuable in itself, independently of its utility. Edition: current; Page: [243] It is thus that wealth becomes, with many, an ultimate object of pursuit; although, at first, it is undoubtedly valued merely on account of its subserviency to the attainment of other objects. In like manner, men are led to desire dress, equipage, retinue, furniture, on account of the estimation in which they are supposed to be held by the public. Such desires are called by Dr Hutcheson1 secondary desires, and their origin is explained by him in the way which I have mentioned. “Since we are capable,” says he, “of reflection, memory, observation, and reasoning, about the distant tendencies of objects and actions, and not confined to things present, there must arise, in consequence of our original desires, secondary desires of everything imagined useful to gratify any of the primary desires; and that with strength proportioned to the several original desires, and imagined usefulness or necessity of the advantageous object.” “Thus,” he continues, “as soon as we come to apprehend the use of wealth or power to gratify any of our original desires, we must also desire them; and hence arises the universality of these desires of wealth and power, since they are the means of gratifying all other desires.” The only thing that appears to me exceptionable in the foregoing passage is, that the author classes the desire of power with that of wealth; whereas I apprehend Edition: current; Page: [244] it to be clear (for reasons which I shall state in another part of this work) that the former is a primary desire, and the latter a secondary one.

Our moral judgments, too, may be modified, and even perverted to a certain degree, in consequence of the operation of the same principle. In the same manner in which a person who is regarded as a model of taste may introduce, by his example, an absurd or fantastical dress; so a man of splendid virtues may attract some esteem also to his imperfections; and, if placed in a conspicuous situation, may render his vices and follies objects of general imitation among the multitude.

“In the reign of Charles II.,” says Mr Smith,1 “a degree of licentiousness was deemed the characteristic of a liberal education. It was connected, according to the notions of those times, with generosity, sincerity, magnanimity, loyalty; and proved that the person who acted in this manner was a gentleman, and not a puritan. Severity of manners and regularity of conduct, on the other hand, were altogether unfashionable, and were connected, in the imagination of that age, with cant, cunning, hypocrisy, and low manners. To superficial minds, the vices of the great seem at all times agreeable. They connect them not only with the splendour of fortune, but with many superior virtues which they ascribe to their superiors; with Edition: current; Page: [245] the spirit of freedom and independency; with frankness, generosity, humanity, and politeness. The virtues of the inferior ranks of people, on the contrary,—their parsimonious frugality, their painful industry, and rigid adherence to rules, seem to them mean and disagreeable. They connect them both with the meanness of the station to which these qualities commonly belong, and with many great vices which they suppose usually accompany them, such as an abject, cowardly, ill-natured, lying, pilfering disposition.”

The theory which, in the foregoing passages from Hutcheson and Smith, is employed so justly and philosophically to explain the origin of our secondary desires, and to account for some perversions of our moral judgments, has been thought sufficient, by some later writers, to account for the origin of all our active principles without exception. The first of these attempts to extend so very far the application of the doctrine of Association, was made by the Rev. Mr Gay, in a Dissertation concerning the Fundamental Principle of Virtue, which is prefixed by Dr Law to his translation of Archbishop King’s Essay on the Origin of Evil. In this dissertation, the author endeavours to shew, “that our approbation of morality, and all affections whatsoever, are finally resolvable into reason, pointing out private happiness, and are conversant only about things apprehended to be means tending Edition: current; Page: [246] to this end; and that wherever this end is not perceived, they are to be accounted for from the association of ideas, and may properly be called habits.” The same principles have been since pushed to a much greater length by Dr Hartley, whose system (as he himself informs us) took rise from his accidentally hearing it mentioned as an opinion of Mr Gay, “that the association of ideas was sufficient to account for all our intellectual pleasures and pains.”1

It must, I think, in justice be acknowledged, that this theory concerning the origin of our affections, and of the moral sense, is a most ingenious refinement upon the selfish system, as it was formerly taught; and that, by means of it, the force of many of the common reasonings against that system is eluded. Among these reasonings, particular stress has always been laid on the instantaneousness with which our affections operate, and the moral sense approves or condemns; and on our total want of consciousness, in such cases, of any reference to our own happiness. The modern advocates for the selfish system admit the fact to be as it is stated by their opponents, and Edition: current; Page: [247] grant that, after the moral sense and our various affections are formed, their exercise, in particular cases, may become completely disinterested; but still they contend, that it is upon a regard to our own happiness that all these principles are originally grafted. The analogy of avarice will serve to illustrate the scope of this theory. It cannot be doubted that this principle of action is artificial. It is on account of the enjoyments which it enables us to purchase that money is originally desired; and yet, in process of time, by means of the agreeable impressions which are associated with it, it comes to be desired for its own sake, and even continues to be an object of our pursuit, long after we have lost all relish for those enjoyments which it enables us to command.

Without meaning to engage in any controversy on the subject, I shall content myself with observing in general, that there must be some limit beyond which the theory of association cannot possibly be carried; for the explanation which it gives of the formation of new principles of action, proceeds on the supposition that there are other principles previously existing in the mind. The great question then is, when are we arrived at this limit; or, in other words, when are we arrived at the simple and original laws of our constitution?

In conducting this inquiry philosophers have been apt to go into extremes. Lord Kames and some other Edition: current; Page: [248] authors have been censured, and perhaps justly, for a disposition to multiply original principles to an unnecessary degree. It may be questioned whether Dr Hartley and his followers have not sometimes been misled by too eager a desire of abridging their number.

Of these two errors the former is the least common and the least dangerous. It is the least common, because it is not so flattering as the other to the vanity of a theorist; and it is the least dangerous, because it has no tendency, like the other, to give rise to a suppression or to a misrepresentation of facts, or to retard the progress of the science by bestowing upon it an appearance of systematical perfection, to which in its present state it is not entitled.

Abstracting, however, from these inconveniences which must always result from a precipitate reference of phenomena to general principles, it does not seem to me that the theory in question has any tendency to weaken the foundation of morals. It has, indeed, some tendency, in common with the philosophy of Hobbes and of Mandeville, to degrade the dignity of human nature, but it leads to no sceptical conclusions concerning the rule of life. For, although we were to grant that all our principles of action are acquired, so striking a difference among them must still be admitted, as is sufficient to distinguish clearly those universal Edition: current; Page: [249] laws which were intended to regulate human conduct, from the local habits which are formed by education and fashion. It must still be admitted that while some active principles are confined to particular individuals, or to particular tribes of men, there are others which, arising from circumstances in which all the situations of mankind must agree, are common to the whole species. Such active principles as fall under this last description, at whatever period of life they may appear, are to be regarded as a part of human nature no less than the instinct of suction; in the same manner as the acquired perception of distance by the eye, is to be ranked among the perceptive powers of man, no less than the original perceptions of any of our other senses.1


1. It is by the immediate evidence of consciousness that we are assured of the present existence of our various sensations, whether pleasant or painful; of all our affections, passions, hopes, fears, desires, and volitions. It is thus, too, we are assured of the present existence of those thoughts which, during Edition: current; Page: [250] our waking hours, are continually passing through the mind, and of all the different effects which they produce in furnishing employment to our intellectual faculties.

According to the common doctrine of our best philosophers, it is by the evidence of consciousness we are assured that we ourselves exist. The proposition, however, when thus stated, is not accurately true; for our own existence (as I have elsewhere observed) is not a direct or immediate object of consciousness, in the strict and logical meaning of that term. We are conscious of sensation, thought, desire, volition; but we are not conscious of the existence of Mind itself; nor would it be possible for us to arrive at the knowledge of it, (supposing us to be created in the full possession of all the intellectual capacities which belong to human nature), if no impression were ever to be made on our external senses. The moment that, in consequence of such an impression, a sensation is excited, we learn two facts at once,—the existence of the sensation, and our own existence as sentient beings;—in other words, the very first exercise of consciousness necessarily implies a belief, not only of the present existence of what is felt, but of the present existence of that which feels and thinks: or (to employ plainer language) the present existence of that being which I denote by the words I and myself. Of these facts, however, it is the former Edition: current; Page: [251] alone of which we can properly be said to be conscious, agreeably to the rigorous interpretation of the expression. A conviction of the latter, although it seems to be so inseparable from the exercise of consciousness that it can scarcely be considered as posterior to it in the order of time, is yet (if I may be allowed to make use of a scholastic distinction) posterior to it in the order of nature; not only as it supposes consciousness to be already awakened by some sensation, or some other mental affection; but as it is evidently rather a judgment accompanying the exercise of that power, than one of its immediate intimations concerning its appropriate class of internal phenomena. It appears to me, therefore, more correct to call the belief of our own existence a concomitant or accessory of the exercise of consciousness, than to say, that our existence is a fact falling under the immediate cognizance of consciousness, like the existence of the various agreeable or painful sensations which external objects excite in our minds.

2. That we cannot, without a very blameable latitude in the use of words, be said to be conscious of our personal identity, is a proposition still more indisputable; inasmuch as the very idea of personal identity involves the idea of time, and consequently presupposes the exercise not only of consciousness, but of memory. The belief connected with this idea is implied in every thought and every action Edition: current; Page: [252] of the mind, and may be justly regarded as one of the simplest and most essential elements of the understanding. Indeed, it is impossible to conceive either an intellectual or an active being to exist without it. It is, however, extremely worthy of remark, with respect to this belief that, universal as it is among our species, nobody but a metaphysician ever thinks of expressing it in words, or of reducing into the shape of a proposition the truth to which it relates. To the rest of mankind, it forms not an object of knowledge; but a condition or supposition, necessarily and unconsciously involved in the exercise of all their faculties. On a part of our constitution, which is obviously one of the last or primordial elements at which it is possible to arrive in analyzing our intellectual operations, it is plainly unphilosophical to suppose that any new light can be thrown by metaphysical discussion. All that can be done with propriety, in such cases, is to state the fact.

And here, I cannot help taking notice of the absurd and inconsistent attempts which some ingenious men have made, to explain the gradual process by which they suppose the mind to be led to the knowledge of its own existence, and of that continued identity which our constitution leads us to ascribe to it. How (it has been asked) does a child come to form the very abstract and metaphysical idea expressed by the pronoun I or moi? Edition: current; Page: [253] In answer to this question, I have only to observe, that when we set about the explanation of a phenomenon, we must proceed on the supposition that it is possible to resolve it into some more general law or laws with which we are already acquainted. But, in the case before us, how can this be expected, by those who consider that all our knowledge of mind is derived from the exercise of reflection; and that every act of this power implies a conviction of our own existence as reflecting and intelligent beings? Every theory, therefore, which pretends to account for this conviction, must necessarily involve that sort of paralogism which logicians call a petitio principii; inasmuch as it must resolve the thing to be explained into some law or laws, the evidence of which rests ultimately on the assumption in question. From this assumption, which is necessarily implied in the joint exercise of consciousness and memory, the philosophy of the human mind, if we mean to study it analytically, must of necessity set out; and the very attempt to dig deeper for its foundation, betrays a total ignorance of the logical rules, according to which alone it can ever be prosecuted with any hopes of success.

It was, I believe, first marked by M. Prévost of Geneva, (and the remark, obvious as it may appear, reflects much honour on his acuteness and sagacity), that the inquiries concerning the mind, founded on Edition: current; Page: [254] the hypothesis of the animated statue—inquiries which both Bonnet and Condillac professed to carry on analytically—were in truth altogether synthetical. To this criticism it may be added, that their inquiries, in so far as they had for their object to explain the origin of our belief of our own existence, and of our personal identity, assumed, as the principles of their synthesis, facts at once less certain and less familiar than the problem which they were employed to resolve.

Nor is it to the metaphysician only that the ideas of identity and of personality are familiar. Where is the individual who has not experienced their powerful influence over his imagination, while he was employed in reflecting on the train of events which have filled up the past history of his life; and on that internal world, the phenomena of which have been exposed to his own inspection alone? On such an occasion, even the wonders of external nature seem comparatively insignificant; and one is tempted, (with a celebrated French writer), in contemplating the spectacle of the universe, to adopt the words of the Doge of Genoa, when he visited Versailles—“Ce qui m’étonne le plus ici, c’est de m’y voir.”1

3. The belief which all men entertain of the existence of the material world, (I mean their belief of its existence independently of that of percipient Edition: current; Page: [255] beings,) and their expectation of the continued uniformity of the laws of nature, belong to the same class of ultimate or elemental laws of thought, with those which have been just mentioned. The truths which form their objects are of an order so radically different from what are commonly called truths, in the popular acceptation of that word, that it might perhaps be useful for logicians to distinguish them by some appropriate appellation, such, for example, as that of metaphysical or transcendental truths. They are not principles or data (as will afterwards appear) from which any consequence can be deduced; but form a part of those original stamina of human reason, which are equally essential to all the pursuits of science, and to all the active concerns of life.

4. I shall only take notice farther, under this head, of the confidence which we must necessarily repose in the evidence of memory, (and, I may add, in the continuance of our personal identity,) when we are employed in carrying on any process of deduction or argumentation,—in following out, for instance, the steps of a long mathematical demonstration. In yielding our assent to the conclusion to which such a demonstration leads, we evidently trust to the fidelity with which our memory has connected the different links of the chain together. The reference which is often made, in the course of a demonstration, to propositions formerly proved, Edition: current; Page: [256] places the same remark in a light still stronger; and shews plainly that, in this branch of knowledge, which is justly considered as the most certain of any, the authority of the same laws of belief which are recognised in the ordinary pursuits of life is tacitly acknowledged. Deny the evidence of memory as a ground of certain knowledge, and you destroy the foundations of mathematical science as completely as if you were to deny the truth of the axioms assumed by Euclid.

The foregoing examples sufficiently illustrate the nature of that class of truths which I have called Fundamental Laws of Human Belief, or Primary Elements of Human Reason. A variety of others, not less important, might be added to the list;1 but these I shall not at present stop to enumerate, as my chief object, in introducing the subject here, was to explain the common relation in which they all stand to deductive evidence. In this point of view, two analogies, or rather coincidences, between the truths which we have been last considering, and the mathematical axioms which were treated of formerly, immediately present themselves to our notice.

1. From neither of these classes of truths can any direct inference be drawn for the farther enlargement of our knowledge. This remark has Edition: current; Page: [257] been already shewn to hold universally with respect to the axioms of geometry, and it applies equally to what I have called Fundamental Laws of Human Belief. From such propositions as these—I exist; I am the same person to-day that I was yesterday; the material world has an existence independent of my mind; the general laws of nature will continue, in future, to operate uniformly as in time past—no inference can be deduced, any more than from the intuitive truths prefixed to the Elements of Euclid. Abstracted from other data, they are perfectly barren in themselves; nor can any possible combination of them help the mind forward one single step in its progress. It is for this reason that, instead of calling them, with some other writers, first principles, I have distinguished them by the title of fundamental laws of belief; the former word seeming to me to denote, according to common usage, some fact, or some supposition, from which a series of consequences may be deduced.

If the account now given of these laws of belief be just, the great argument which has been commonly urged in support of their authority, and which manifestly confounds them with what are properly called principles of reasoning, is not at all applicable to the subject; or at least does not rest the point in dispute upon its right foundation. If there were no first principles, (it has been said,) or in other Edition: current; Page: [258] words, if a reason could be given for everything, no process of deduction could possibly be brought to a conclusion. The remark is indisputably true; but it only proves (what no logician of the present times will venture to deny) that the mathematician could not demonstrate a single theorem, unless he were first allowed to lay down his definitions; nor the natural philosopher explain or account for a single phenomenon, unless he were allowed to assume, as acknowledged facts, certain general laws of nature. What inference does this afford in favour of that particular class of truths to which the preceding observations relate, and against which the ingenuity of modern sceptics has been more particularly directed? If I be not deceived, these truths are still more intimately connected with the operations of the reasoning faculty than has been generally imagined; not as the principles (ἀρχαί) from which our reasonings set out, and on which they ultimately depend, but as the necessary conditions on which every step of the deduction tacitly proceeds; or rather (if I may use the expression) as essential elements which enter into the composition of reason itself.

2. In this last remark I have anticipated, in some measure, what I had to state with respect to the second coincidence alluded to, between mathematical axioms, and the other propositions which I have comprehended under the general title of Edition: current; Page: [259] fundamental laws of human belief. As the truth of axioms is virtually presupposed or implied in the successive steps of every demonstration, so, in every step of our reasonings concerning the order of Nature, we proceed on the supposition, that the laws by which it is regulated will continue uniform as in time past; and that the material universe has an existence independent of our perceptions. I need scarcely add, that in all our reasonings whatever, whether they relate to necessary or to contingent truths, our own personal identity, and the evidence of memory, are virtually taken for granted. These different truths all agree in this, that they are essentially involved in the exercise of our rational powers; although, in themselves, they furnish no principles or data by which the sphere of our knowledge can, by any ingenuity, be enlarged. They agree farther in being tacitly acknowledged by all men, learned or ignorant, without any formal enunciation in words, or even any conscious exercise of reflection. It is only at that period of our intellectual progress when scientific arrangements and metaphysical refinements begin to be introduced, that they become objects of attention to the mind, and assume the form of propositions.

In consequence of these two analogies or coincidences, I should have been inclined to comprehend, under the general title of axioms, all the truths which have been hitherto under our review, if the Edition: current; Page: [260] common usage of our language had not, in a great measure, appropriated that appellation to the axioms of mathematics; and if the view of the subject which I have taken, did not render it necessary for me to direct the attention of my readers to the wide diversity between the branches of knowledge to which they are respectively subservient.

I was anxious also to prevent these truths from being all identified, in point of logical importance, under the same name. The fact is, that the one class (in consequence of the relation in which they stand to the demonstrative conclusions of geometry) are comparatively of so little moment, that the formal enumeration of them was a matter of choice rather than of necessity; whereas the other class have unfortunately been raised, by the sceptical controversies of modern times, to a conspicuous rank in the philosophy of the human mind. I have thought it more advisable, therefore, to bestow on the latter an appropriate title of their own; without, however, going so far as to reject altogether the phraseology of those who have annexed to the word axiom a more enlarged meaning than that which I have usually given to it. Little inconvenience, indeed, can arise from this latitude in the use of the term; provided only it be always confined to those ultimate laws of belief, which, although they form the first elements of human reason, cannot with propriety be ranked Edition: current; Page: [261] among the principles from which any of our scientific conclusions are deduced.

Corresponding to the extension which some late writers have given to axioms, is that of the province which they have assigned to intuition; a term which has been applied, by Dr Beattie and others, not only to the power by which we perceive the truth of the axioms of geometry, but to that by which we recognise the authority of the fundamental laws of belief, when we hear them enunciated in language. My only objection to this use of the word is, that it is a departure from common practice; according to which, if I be not mistaken, the proper objects of intuition are propositions analogous to the axioms prefixed to Euclid’s Elements. In some other respects, this innovation might perhaps be regarded as an improvement on the very limited and imperfect vocabulary of which we are able to avail ourselves in our present discussions.1

Edition: current; Page: [262]

To the class of truths which I have here called laws of belief, or elements of reason, the title of principles of common sense was long ago given by Father Buffier, whose language and doctrine concerning them bears a very striking resemblance to those of some of our later Scottish logicians. This, at least, strikes me as the meaning which these writers in general annex to the phrase, although all of them have frequently employed it with a far greater degree of latitude. When thus limited in its acceptation, it is obviously liable, in point of scientific accuracy, to two very strong objections, both of which have been already sufficiently illustrated. The first is, that it applies the appellation of principles to laws of belief from which no inference can be deduced; the second, that it refers the origin of these laws to Common Sense. Nor is this phraseology more agreeable to popular use than to logical precision. If we were to suppose an individual, whose conduct betrayed a disbelief of his own existence, or of his own identity, or of the reality of surrounding objects, it would by no means amount to an adequate description of his condition to say, that he was destitute of common sense. We should at once pronounce him to be destitute of reason, and would no longer consider him as a fit subject of discipline or of punishment. The former expression, indeed, would only imply that he was apt to fall into absurdities Edition: current; Page: [263] and improprieties in the common concerns of life. To denominate, therefore, such laws of belief as we have now been considering, constituent elements of human reason, while it seems quite unexceptionable in point of technical distinctness, cannot be justly censured as the slightest deviation from our habitual forms of speech. On the same grounds, it may be fairly questioned, whether the word reason would not, on some occasions, be the best substitute which our language affords for intuition, in that enlarged acceptation which has been given to it of late. If not quite so definite and precise as might be wished, it would be at least employed in one of those significations in which it is already familiar to every ear; whereas the meaning of intuition, when used for the same purpose, is stretched very far beyond its ordinary limits. And in cases of this sort, where we have to choose between two terms, neither of which is altogether unexceptionable, it will be found much safer to trust to the context for restricting in the reader’s mind what is too general, than for enlarging what use has accustomed us to interpret in a sense too narrow.

I must add, too, in opposition to the high authorities of Dr Johnson and Dr Beattie, that for many years past, reason has been very seldom used by philosophical writers, or, indeed, by correct writers of any description, as synonymous with the power of reasoning. To appeal to the light of human Edition: current; Page: [264] reason from the reasonings of the schools, is surely an expression to which no good objection can be made, on the score either of vagueness or of novelty. Nor has the etymological affinity between these two words the slightest tendency to throw any obscurity on the foregoing expression. On the contrary, this affinity may be of use in some of our future arguments, by keeping constantly in view the close and inseparable connexion which will be afterwards shown to exist between the two different intellectual operations which are thus brought into immediate contrast.1

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Thomas Reid was born in 1710 at Strachan in Kincardineshire. His father was minister of the parish. At the age of twelve, Reid entered Marischal College, Aberdeen, but did not profit much by the teaching. After graduating in Arts, he studied Divinity, and was licensed to preach in 1731. In 1733 he was appointed Librarian of Marischal College, and in 1737 was presented by King’s College to the living of New Machar, near Aberdeen. At first his parishioners were very hostile, tradition saying that his uncle had to guard the pulpit stairs with a drawn sword. But their prejudices were gradually overcome by Reid’s practical benevolence, though to the end they were dissatisfied with his sermons, which they regarded as not sufficiently original. In 1751 Reid was appointed a regent at King’s College, and became “Professor of Philosophy,” his lectures including mathematics and physics. He was one of the founders of the Aberdeen Philosophical Society (“The Wise Club”), which included among its members Beattie and Campbell. It was in this society that Reid developed his philosophy. His point of view was made known to the club in several papers, which were systematised in the Inquiry into the Human Mind on the Principles of Common Sense. This was published in 1764, the year in which Reid succeeded Adam Smith as Professor of Moral Philosophy in the University of Glasgow. The next sixteen years were fully occupied with the duties of his chair and University business. In 1780 he retired from his active University work, in order to complete his philosophical system. In 1785 appeared the Essays on the Intellectual Powers of Man, and three years later the Essays on the Active Powers of Man. The last years of his life were devoted to mathematics and gardening, and in 1796 he died.


Works, vol. 1. p. 95.


Works, vol. i. p. 96.


Reid’s Works, vol. ii. p. 751.


Mind, 1895, p. 153.


Works, vol. i. p. 98.


Ibid., p. 106.


Works, vol. i. p. 110.


Ibid., vol. i. p. 123.


Works, vol. i. p. 122.


Ibid., vol. i. p. 137.


James Beattie was born in 1735, and in 1749 went to Marischal College, Aberdeen. His circumstances were narrow, and on graduation he took a post as schoolmaster at Fordoun, Kincardineshire, where he became acquainted with Lord Monboddo. In 1760 he was appointed Professor of Moral Philosophy in Marischal College, where he became a member of Reid’s “Wise Club.” Beattie was a poet by choice and a philosopher only by profession. He himself preferred his poetry to his philosophy, but in this judgment he was not supported by the public. The Essay on Truth, published in 1770, passed through five large editions in four years. Beattie came to be regarded as the defender of the faith, and all sorts of honours were showered on him. He continued to lecture at Aberdeen till 1797, when he became too ill to do even occasional lecturing. He died in 1803.


Adam Ferguson was born in 1723 at Logierait, Perthshire, where his father was minister of the parish. Passing through the Universities of St Andrews and Edinburgh, he was appointed in 1745 Chaplain to the Black Watch, being present at the battle of Fontenoy, and, according to legend, leading the regiment into action, drawn broadsword in hand. In 1757 he succeeded Hume in the Librarianship of the Advocates’ Library, which he held for less than a year. In 1759 he became Professor of Natural Philosophy in Edinburgh University, and in 1764 was transferred to the chair of moral philosophy. He contrived, while retaining his chair, to engage in several controversies, undertake the tuition of noblemen’s sons, and perform various Government services, involving trips on the Continent and to Philadelphia. He resigned his Professorship in 1785, and died in 1816. His works include Essay on Civil Society (1766), Institutes of Moral Philosophy (1772), Principles of Moral and Political Science (1792).


Dugald Stewart was born in 1753 at Edinburgh, where his father was Professor of Mathematics. In 1765 he entered the University, became a good mathematician, and came under the influence of Adam Ferguson. Ferguson had warmly welcomed Reid’s Inquiry, and thus from the beginning Stewart was brought to regard Reid as the chief authority in philosophy. In 1771 he went to Glasgow and attended Reid’s lectures. The next session saw him again in Edinburgh, taking charge of his father’s mathematical classes. In 1785 he was transferred to the chair of moral philosophy. He rapidly acquired great influence both in the general society of Edinburgh, and in the philosophical world. James Mill says that neither Pitt nor Fox was nearly so eloquent. He was a prolific writer, beginning with the Elements of the Philosophy of the Human Mind, the first volume of which was published in 1792, and ending with the Philosophy of the Active and Moral Powers of Man in 1828. He retired from the active duties of the chair in 1809; and thenceforward, till his death in 1828, occupied himself with literary work.


“Inquiry into the Human Mind,” Works, vol. 1. pp. 97-99.


Ibid., pp. 100-101.


Ibid., p. 101.


Ibid., pp. 105-115.


Ibid., pp. 121-122.


Ibid., pp. 123-125.


Ibid., p. 135.


Ibid., pp. 137-138.


Ibid., pp. 142-143.


Ibid., p. 146.


Ibid., pp. 182-183.


Ibid., pp. 184-186.


Ibid., p. 187.


“Letter to Lord Kames,” 16th Dec. 1780 (Works, vol. i. pp. 56-59).


“Essays on the Active Powers of Man” (Works, vol. ii. pp. 522-525).


“Essays on the Intellectual Powers of Man” (Works, vol. i. p. 230).


Ibid., p. 232.


Ibid., p. 233.


Ibid., p. 234.


Ibid., p. 236.


Ibid., p. 238.


Ibid., p. 258.


Ibid., pp. 259-260.


Ibid., p. 310.


Ibid., p. 312.


Ibid., pp. 313-314.


Ibid., pp. 360-361.


Ibid., p. 363.


Ibid., pp. 365-366.


Ibid., p. 368.


Ibid., pp. 414-415.


Ibid., pp. 416-417.


Ibid., pp. 418-421.


Ibid., pp. 422-423.


Ibid., pp. 425-426.


Ibid., pp. 441-452. (In reprinting this and the following section some passages have been silently omitted.)


Ibid., pp. 452-457.


“Essays on the Active Powers of Man,” Works, vol. ii. pp. 558-560. (In reprinting this and the following sections on Morals several passages have been silently omitted.)


Ibid., pp. 579-580.


Ibid., pp. 580-581.


Ibid., pp. 586-590.


Ibid., pp. 594-599.


Ibid., pp. 670-673.


Principles of Moral and Political Science, vol. 1. pp. 189-202


Essay on the Nature and Immutability of Truth, pp. 22-27.


Ibid., pp. 31-35.


Ibid., pp. 38-40.


“Outlines of Moral Philosophy,” Works, vol. ii. pp. 5-8.


Ibid., pp. 23-25


By Lord Kames and others.


“Elements of the Philosophy of the Human Mind,” Works, vol. ii. pp. 266-269.


See his Essay on the Nature and Conduct of the Passions.


Theory of Moral Sentiments.


Mr Hume, too, who in my opinion has carried this principle of the Association of Ideas a great deal too far, had compared the universality of its applications in the philosophy of mind, to that of the principle of attraction in physics. “Here,” says he, “is a kind of attraction, which in the mental world will be found to have as extraordinary effects as in the natural, and to shew itself in as many and as various forms.”—Treatise of Human Nature, vol. i. p. 30.


“Elements of the Philosophy of the Human Mind,” Works, vol. ii. pp. 334-338.


D’Alembert, Apologie de l’Étude.


Such, for example, as our belief of the existence of efficient causes; our belief of the existence of other intelligent beings besides ourselves, etc., etc.


According to Locke, we have the knowledge of our own existence by intuition; of the existence of God by demonstration; and of other things by sensation—Book iv. chap. ix. § 2.

This use of the word intuition seems to be somewhat arbitrary. The reality of our own existence is a truth which bears as little analogy to the axioms of mathematics, as any other primary truth whatever. If the province of intuition, therefore, be extended as far as it has been carried by Locke in the foregoing sentence, it will not be easy to give a good reason why it should not be enlarged a little farther. The words intuition and demonstration, it must not be forgotten, have both of them an etymological reference to the sense of seeing; and when we wish to express, in the strongest terms, the most complete evidence which can be set before the mind, we compare it to the light of noon-day;—in other words, we compare it to what Mr Locke here attempts to degrade, by calling it the evidence of sensation.


“Elements of the Philosophy of the Human Mind,” (Works, vol. iii. pp. 40-51).