The Online Library of Liberty

A project of Liberty Fund, Inc.

• Dedication
• Preface 1
• Translator’s Preface
• Translator’s Preface to Second Edition
• Introduction [p. 1]
• I: The Idea of Transcendental Philosophy
• II: Division of Transcendental Philosophy
• I: The Elements of Transcendentalism
• Part I: Transcendental Æsthetic [p. 19]
• Section I: Of Space
• Section II: Of Time
• Part II: Transcendental Logic [p. 50]
• Introduction the Idea of a Transcendental Logic
• I: Of Logic In General
• II: Of Transcendental Logic
• III: Of the Division of General Logic Into Analytic and Dialectic
• IV: Of the Division of Transcendental Logic Into Transcendental Analytic and Dialectic
• Division I: Transcendental Analytic In Two Books, With Their Chapters and Sections
• Book I: Analytic of Concepts
• Chapter I: Method of Discovering All Pure Concepts of the Understanding
• Section I: Of the Logical Use of the Understanding In General
• Section II: Of the Logical Function of the Understanding In Judgments [p. 70]
• Section III: Of the Pure Concepts of the Understanding, Or of the Categories
• Chapter II: Of the Deduction of the Pure Concepts of the Understanding [p. 84]
• Section I: Of the Principles of a Transcendental Deduction In General
• Section II: Of the a Priori Grounds For the Possibility of Experience
• I: Of the Synthesis of Apprehension In Intuition
• II: Of the Synthesis of Reproduction In Imagination
• III: Of the Synthesis of Recognition In Concepts [p. 103]
• IV: Preliminary Explanation of the Possibility of the Categories As Knowledge a Priori
• Section III: Of the Relation of the Understanding to Objects In General, and the Possibility of Knowing Them a Priori [p. 115]
• Book II: Analytic of Principles
• Introduction of the Transcendental Faculty of Judgment In General
• Chapter I: Of the Schematism of the Pure Concepts of the Understanding [p. 137]
• Chapter II: System of All Principles of the Pure Understanding [p. 148]
• Section I: Of the Highest Principle of All Analytical Judgments
• Section II: Of the Highest Principle of All Synthetical Judgments [p. 154]
• Section III: Systematical Representation of All Synthetical Principles of the Understanding
• I: [of the Axioms of Intuition 1 Principle of the Pure Understanding
• II: [ Anticipations of Perception
• III: [ the Analogies of Experience
• IV: The Postulates of Empirical Thought In General
• Chapter III: On the Ground of Distinction of All Subjects Into Phenomena and Noumena
• I.: Identity and Difference
• II.: Agreement and Opposition
• III.: The Internal and the External
• IV.: Matter and Form
• Note On the Amphiboly of Reflective Concepts
• Division II: Transcendental Dialectic In Two Books, With Their Chapters and Sections [p. 293]
• Introduction: 1.
• Book I: Of the Concepts of Pure Reason [p. 310]
• First Section of Ideas In General
• Second Section of Transcendental Ideas [p. 321]
• Third Section System of Transcendental Ideas [p. 333]
• Book II: Of the Dialectical Conclusions of Pure Reason
• Chapter I: Of the Paralogisms of Pure Reason [p. 341]
• Chapter II: The Antinomy of Pure Reason
• Section I: System of Cosmological Ideas
• Section II: Antithetic of Pure Reason
• Section III: Of the Interest of Reason In These Conflicts [p. 462]
• Section IV: Of the Transcendental Problems of Pure Reason, and the Absolute Necessity of Their Solution
• Section V: Sceptical Representation of the Cosmological Questions In the Four Transcendental Ideas [p. 485]
• Section VI: Transcendental Idealism As the Key to the Solution of Cosmological Dialectic
• Section VII: Critical Decision of the Cosmological Conflict of Reason With Itself
• Section VIII: The Regulative Principle of Pure Reason With Regard to the Cosmological Ideas [p. 508]
• Section IX: Of the Empirical Use of the Regulative Principle of Reason With Regard to All Cosmological Ideas
• Chapter III: The Ideal of Pure Reason
• Section I: Of the Ideal In General
• Section II: Of the Transcendental Ideal ( Prototypon Transcendentale )
• Section III: Of the Arguments of Speculative Reason In Proof of the Existence of a Supreme Being
• Section IV: Of the Impossibility of an Ontological Proof of the Existence of God [p. 592]
• Section V: Of the Impossibility of a Cosmological Proof of the Existence of God [p. 603]
• Section VI: Of the Impossibility of the Physico-theological Proof
• Section VII: Criticism of All Theology Based On Speculative Principles of Reason [p. 631]
• Chapter I: The Discipline of Pure Reason
• Section I: The Discipline of Pure Reason In Its Dogmatical Use
• Section II: The Discipline of Pure Reason In Its Polemical Use
• Section III: The Discipline of Pure Reason With Regard to Hypotheses
• Section IV: The Discipline of Pure Reason With Regard to Its Proofs
• Chapter II: The Canon of Pure Reason [p. 795]
• First Section: of the Ultimate Aim of the Pure Use of Our Reason
• Section II: Of the Ideal of the Summum Bonum As Determining the Ultimate Aim of Pure Reason
• Section III: Of Trowing, Knowing, and Believing [p. 820]
• Chapter III: The Architectonic of Pure Reason [p. 832]
• Chapter IV: The History of Pure Reason [p. 852]
• Supplement I: Motto to Second Edition
• Supplement II: Preface to the Second Edition. 1787. [p. Vii]
• Supplement III: Supplement Iv
• Supplement V
• Supplement Vi
• Supplement V
• Supplement Vi
• Supplement Vii
• Supplement Viii
• Supplement Ix
• Supplement X
• Supplement Xi
• Supplement Xii
• Supplement Xiii
• Supplement Xiv
• Supplement Xv
• Supplement Xvi a
• Supplement Xvi B
• Supplement Xvii
• Supplement Xviii
• Supplement Xix
• Supplement Xx
• Supplement Xxi
• Supplement Xxii
• Supplement Xxiii
• Supplement Xxiv
• Supplement Xxv
• Supplement Xxvi
• Supplement Xxvii
• Supplement Xxviii

First Section

Of the Ultimate Aim of the Pure Use of our Reason

Reason is impelled by a tendency of its nature to go beyond the field of experience, and to venture in its pure employment and by means of mere ideas to the utmost limits of all knowledge; nay, it finds no rest until it has fulfilled its course and established an independent and systematic whole of all knowledge. The question is, whether this endeavour rests on the speculative, or rather, exclusively on the practical interests of reason?

I shall say nothing at present of the success which has attended pure reason in its speculative endeavours, and only ask which are the problems, the solution of which forms its ultimate aim (whether that object be really reached or not), and in relation to which all other problems are only means to an end. These highest aims must again, according to the nature of reason, possess [p. 798] a certain unity in order to advance by their union that interest of humanity which is second to no other.

The highest aim to which the speculation of reason in its transcendental employment is directed comprehends three objects: the freedom of the will, the immortality of the soul, and the existence of God. The purely speculative interest of reason in every one of these three questions is very small, and, for its sake alone, this fatiguing and ceaseless labour of transcendental investigation would hardly have been undertaken, because whatever discoveries may be made, they could never be used in a way that would be advantageous in concreto, that is, in the investigation of nature.

Our will may be free, but this would only refer to the intelligible cause of our volition. With regard to the phenomena in which that will manifests itself, that is, our actions, we have to account for them (according to an inviolable maxim without which reason could not be employed for empirical purposes at all), in no other way than for all other phenomena of nature, that is, according to her unchangeable laws.

Secondly, the spiritual nature of the soul, and with it its immortality, may be understood by us, yet we could not base upon this any explanation, either with regard to the phenomena of this life, or the peculiar nature of a [p. 799] future state, because our concept of an incorporeal nature is purely negative and does not expand our knowledge in the least, nor does it offer any fit material for drawing consequences, except such as are purely fictitious, and could never be countenanced by philosophy.

Thirdly, even admitting that the existence of a highest intelligence had been proved, we might, no doubt, use it in order to make the design in the constitution of the world and its order in general intelligible, but we should never be justified in deriving from it any particular arrangement, or disposition, or in boldly inferring it where it cannot be perceived. For it is a necessary rule for the speculative employment of reason, never to pass by natural causes, and, abandoning what we may learn from experience, to derive something which we know, from something which entirely transcends all our knowledge.

In one word, these three propositions remain always transcendent for speculative reason, and admit of no immanent employment, that is, an employment admissible for objects of experience, and therefore of some real utility to ourselves, but are by themselves entirely valueless and yet extremely difficult exertions of our reason.

If, therefore, these three cardinal propositions are of no use to us, so far as knowledge is concerned, and are yet so strongly recommended to us by our reason, their true value will probably be connected with our [p. 800] practical interests only.

I call practical whatever is possible through freedom. When the conditions of the exercise of our free-will are empirical, reason can have no other but a regulative use, serving only to bring about the unity of empirical laws. Thus, for instance, in the teaching of prudence, the whole business of reason consists in concentrating all the objects of our desires in one, namely, happiness, and in co-ordinating the means for obtaining it. Reason, therefore, can give us none but pragmatic laws of free action for the attainment of the objects recommended to us by the senses, and never pure laws, determined entirely a priori. Pure practical laws, on the contrary, the object of which is given by reason entirely a priori, and which convey commands, not under empirical conditions, but absolutely, would be products of pure reason. Such are the moral laws, and these alone, therefore, belong to the sphere of the practical use of reason, and admit of a canon.

All the preparations of reason, therefore, in what may be called pure philosophy, are in reality directed to those three problems only. These themselves, however, have a still further object, namely, to know what ought to be done, if the will is free, if there is a God, and if there is a future world. As this concerns our actions with reference to the highest aim of life, we see that the last intention [p. 801] of nature in her wise provision was really, in the constitution of our reason, directed to moral interests only.

We must be careful, however, lest, as we are now considering a subject which is foreign to transcendental philosophy,1 we should lose ourselves in episodes, and injure the unity of the system, while on the other side, if we say too little of this new matter, there might be a lack of clearness and persuasion. I hope to avoid both dangers by keeping as close as possible to what is transcendental, and by leaving entirely aside what may be psychological, that is, empirical in it.

I have, therefore, first to remark that for the present I shall use the concept of freedom in its practical meaning only, taking no account of the other concept of freedom in its transcendental meaning, which cannot be presupposed empirically as an explanation of phenomena, but is itself a problem of reason and has been disposed [p. 802] of before. A will is purely animal (arbitrium brutum) when it is determined by nothing but sensuous impulses, that is, pathologically. A will, on the contrary, which is independent of sensuous impulses, and can be determined therefore by motives presented by reason alone, is called Free-will (arbitrium liberum), and everything connected with this, whether as cause or effect, is called practical. Practical freedom can be proved by experience. For human will is not determined by that only which excites, that is, immediately affects the senses; but we possess the power to overcome the impressions made on the faculty of our sensuous desires, by representing to ourselves what, in a more distant way, may be useful or hurtful. These considerations of what is desirable with regard to our whole state, that is, of what is good and useful, are based entirely on reason. Reason, therefore, gives laws which are imperatives, that is, objective laws of freedom, and tell us what ought to take place, though perhaps it never does take place, differing therein from the laws of nature, which relate only to what does take place. These laws of freedom, therefore, are called practical laws.

Whether reason in prescribing these laws is [p. 803] not itself determined by other influences, and whether what, in relation to sensuous impulses, is called freedom, may not, with regard to higher and more remote causes, be nature again, does not concern us while engaged in these practical questions, and while demanding from reason nothing but the rule of our conduct. It is a purely speculative question which, while we are only concerned with what we ought or ought not to do, may well be left aside. We know practical freedom by experience as one of the natural causes, namely, as a causality of reason in determining the will, while transcendental freedom demands the independence of reason itself (with reference to its causality in beginning a series of phenomena) from all determining causes in the world of sense, thus running counter, as it would seem, to the law of nature and therefore to all possible experience, and remaining a problem. Reason, however, in its practical employment has nothing to do with this problem, so that there remain but two questions in a canon of pure reason which concern the practical interest of pure reason, and with regard to which a canon of their employment must be possible, namely: Is there a God? Is there a future life? The question of transcendental freedom refers to speculative knowledge only, and may be safely left aside as quite indifferent when we are concerned with practical interests. A sufficient discussion [p. 804] of it may be found in the antinomy of pure reason.

[1 ]All practical concepts relate to objects of pleasure or displeasure, that is, of joy or pain, and, therefore, at least indirectly, to objects of our feelings. But, as feeling is not a faculty of representing things, but lies outside the whole field of our powers of cognition, the elements of our judgments, so far as they relate to pleasure or pain, that is, the elements of practical judgments, do not belong to transcendental philosophy, which is concerned exclusively with pure cognitions a priori.