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• Selections From the Scottish Philosophy of Common Sense
• Introduction
• Thomas Reid
• I.—: Introduction to the Philosophy of Common Sense
• § 1.: The Importance of the Subject, and the Means of Prosecuting It
• § 2.: The Impediments to Our Knowledge of the Mind
• II.—: Analysis of a Typical Sensation
• § 1.: The Sensation Considered Abstractly
• § 2.: Sensation and Remembrance, Natural Principles of Belief
• § 3.: Judgment and Belief In Some Cases Precede Simple Apprehension
• § 4.: Two Theories of the Nature of Belief Refuted—conclusions From What Hath Been Said
• § 5.: Apology For Metaphysical Absurdities—sensation Without a Sentient, a Consequence of the Theory of Ideas—consequences of This Strange Opinion
• § 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
• § 7.: There Is a Quality Or Virtue In Bodies, Which We Call Their Smell—how This Is Connected In the Imagination With the Sensation
• § 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
• § 9.: Whether In Sensation the Mind Is Active Or Passive?
• III.—: Knowledge and Reality
• § 1.: Of Hardness
• § 2.: Of Natural Signs
• § 3.: Of Extension
• § 4.: Of the Visible Appearances of Objects
• § 5.: Of Perception In General
• § 6.: Of the Process of Nature In Perception
• Appendix: of Cause and Power
• IV.—: The Operations of the Mind
• § 1.: Principles Taken For Granted
• § 2.: Of Hypotheses and Analogy
• § 3.: Of Perception
• § 4.: Of Sensation
• § 5.: Of Primary and Secondary Qualities
• § 6.: Of Conception
• § 7.: Of Judgment
• § 8.: Of Common Sense
• § 9.: The First Principles of Contingent Truths
• § 10.: First Principles of Necessary Truths
• V.—: Of Morals
• § 1.: Of Benevolent Affection In General
• § 2.: There Are Rational Principles of Action In Man
• § 3.: Of Regard to Our Good On the Whole
• § 4.: Of the Notion of Duty, Rectitude, Moral Obligation
• § 5.: Observations Concerning Conscience
• § 6.: That Moral Approbation Implies a Real Judgment
• Adam Ferguson
• Of Man’s Progressive Nature
• James Beattie
• Of the Perception of Truth In General
• Dugald Stewart
• I.—: Of the Object of Philosophy, and the Method of Prosecuting Philosophical Inquiries
• II.—: Of the Association of Ideas
• III.—: Of the Power Which the Mind Has Over the Train of Its Thoughts
• IV.—: Of the Influence of Association On Our Active Principles, and On Our Moral Judgments
• V.—: Of Certain Laws of Belief, Inseparably Connected With the Exercise of Consciousness, Memory, Perception, and Reasoning

I.—

OF THE OBJECT OF PHILOSOPHY, AND THE METHOD OF PROSECUTING PHILOSOPHICAL INQUIRIES

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 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 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 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 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

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