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

I

Of Logic in General

Our knowledge springs from two fundamental sources of our soul; the first receives representations (receptivity of impressions), the second is the power of knowing an object by these representations (spontaneity of concepts). By the first an object is given us, by the second the object is thought, in relation to that representation which is a mere determination of the soul. Intuition therefore and concepts constitute the elements of all our knowledge, so that neither concepts without an intuition corresponding to them, nor intuition without concepts can yield any real knowledge.

Both are either pure or empirical. They are empirical when sensation, presupposing the actual presence of the object, is contained in it. They are pure when no sensation is mixed up with the representation. The latter may be called the material of sensuous knowledge. Pure intuition therefore contains the form only by which [p. 51] something is seen, and pure conception the form only by which an object is thought. Pure intuitions and pure concepts only are possible a priori, empirical intuitions and empirical concepts a posteriori.

We call sensibility the receptivity of our soul, or its power of receiving representations whenever it is in any wise affected, while the understanding, on the contrary, is with us the power of producing representations, or the spontaneity of knowledge. We are so constituted that our intuition must always be sensuous, and consist of the mode in which we are affected by objects. What enables us to think the objects of our sensuous intuition is the understanding. Neither of these qualities or faculties is preferable to the other. Without sensibility objects would not be given to us, without understanding they would not be thought by us. Thoughts without contents are empty, intuitions without concepts are blind. Therefore it is equally necessary to make our concepts sensuous, i.e. to add to them their object in intuition, as to make our intuitions intelligible, [Editor: illegible word.] bring them under concepts. These two powers or faculties cannot exchange their functions. The understanding cannot see, the senses cannot think. By their union only can knowledge be produced. But this is no reason for confounding the share which belongs to each in the production of knowledge. On the contrary, they should always [p. 52] be carefully separated and distinguished, and we have therefore divided the science of the rules of sensibility in general, i.e. æsthetic, from the science of the rules of the understanding in general, i.e. logic.

Logic again can be taken in hand for two objects, either as logic of the general or of a particular use of the understanding. The former contains all necessary rules of thought without which the understanding cannot be used at all. It treats of the understanding without any regard to the different objects to which it may be directed. Logic of the particular use of the understanding contains rules how to think correctly on certain classes of objects. The former may be called Elementary Logic, the latter the Organum of this or that science. The latter is generally taught in the schools as a preparation for certain sciences, though, according to the real progress of the human understanding, it is the latest achievement, which does not become possible till the science itself is really made, and requires only a few touches for its correction and completion. For it is clear that the objects themselves must be very well known before it is possible to give rules according to which a science of them may be established.

General logic is either pure or applied. In the [p. 53] former no account is taken of any empirical conditions under which our understanding acts, i.e. of the influence of the senses, the play of imagination, the laws of memory, the force of habit, the inclinations, and therefore the sources of prejudice also, nor of anything which supplies or seems to supply particular kinds of knowledge; for all this applies to the understanding under certain circumstances of its application only, and requires experience as a condition of knowledge. General but pure logic has to deal with principles a priori only, and is a canon of the understanding and of reason, though with reference to its formal application only, irrespective of any contents, whether empirical or transcendental. General logic is called applied, if it refers to the rules of the use of our understanding under the subjective empirical conditions laid down in psychology. It therefore contains empirical principles, yet it is general, because referring to the use of the understanding, whatever its objects may be. It is neither a canon of the understanding in general nor an organum of any particular science, but simply a catharticon of the ordinary understanding.

In general logic, therefore, that part which is to constitute the science of pure reason must be entirely separated from that which forms applied, but for all [p. 54] that still general logic. The former alone is a real science, though short and dry, as a practical exposition of an elementary science of the understanding ought to be. In this logicians should never lose sight of two rules:—

1. As general logic it takes no account of the contents of the knowledge of the understanding nor of the difference of its objects. It treats of nothing but the mere form of thought.

2. As pure logic it has nothing to do with empirical principles, and borrows nothing from psychology (as some have imagined); psychology, therefore, has no influence whatever on the canon of the understanding. It proceeds by way of demonstration, and everything in it must be completely a priori.

What I call applied logic (contrary to common usage according to which it contains certain exercises on the rules of pure logic) is a representation of the understanding and of the rules according to which it is necessarily applied in concreto, i.e. under the accidental conditions of the subject, which may hinder or help its application, and are all given empirically only. It treats of attention, its impediments and their consequences, the sources of error, the states of doubt, hesitation, and conviction, etc., and general and pure logic stands to it in [p. 55] the same relation as pure ethics, which treat only of the necessary moral laws of a free will, to applied ethics, which consider these laws as under the influence of sentiments, inclinations, and passions to which all human beings are more or less subject. This can never constitute a true and demonstrated science, because, like applied logic, it depends on empirical and psychological principles.