Kant - Critique of Pure Reason (2)

[ Immanuel Kant - Kritik der reinen Vernunft, 1781 - 856 pages (first German edition) - Subject: Metaphysics ]

The Critique of Pure Reason is arranged around several basic distinctions. After the two Prefaces (the A edition Preface of 1781 and the B edition Preface of 1787) and the Introduction, the book is divided into the Doctrine of Elements and the Doctrine of Method.

Doctrine of Elements and of Method

The Doctrine of Elements sets out the a priori products of the mind, and the correct and incorrect use of these presentations. Kant further divides the Doctrine of Elements into the Transcendental Aesthetic and the Transcendental Logic, reflecting his basic distinction between sensibility and the understanding. In the "Transcendental Aesthetic" he argues that space and time are pure forms of intuition inherent in our faculty of sense. The "Transcendental Logic" is separated into the Transcendental Analytic and the Transcendental Dialectic:

- The Transcendental Analytic sets forth the appropriate uses of a priori concepts, called the categories, and other principles of the understanding, as conditions of the possibility of a science of metaphysics. The section titled the "Metaphysical Deduction" considers the origin of the categories. In the "Transcendental Deduction", Kant then shows the application of the categories to experience.

Next, the "Analytic of Principles" sets out arguments for the relation of the categories to metaphysical principles. This section begins with the "Schematism", which describes how the imagination can apply pure concepts to the object given in sense perception. Next are arguments relating the a priori principles with the schematized categories.

- The Transcendental Dialectic describes the transcendental illusion behind the misuse of these principles in attempts to apply them to realms beyond sense experience. Kant’s most significant arguments are the "Paralogisms of Pure Reason", the "Antinomy of Pure Reason", and the "Ideal of Pure Reason", aimed against, respectively, traditional theories of the soul, the universe as a whole, and the existence of God. In the Appendix to the "Critique of Speculative Theology" Kant describes the role of the transcendental ideas of reason.

The Doctrine of Method contains four sections. The first section, "Discipline of Pure Reason", compares mathematical and logical methods of proof, and the second section, "Canon of Pure Reason", distinguishes theoretical from practical reason.

The divisions of the Critique of Pure Reason

Dedication
1. First and second Prefaces
2. Introduction
3. Transcendental Doctrine of Elements
A. Transcendental Aesthetic
(1) On space
(2) On time
B. Transcendental Logic
(1) Transcendental Analytic
a. Analytic of Concepts
i. Metaphysical Deduction
ii. Transcendental Deduction
b. Analytic of Principles
i. Schematism (bridging chapter)
ii. System of Principles of Pure Understanding
a. Axioms of Intuition
b. Anticipations of Perception
c. Analogies of Experience
d. Postulates of Empirical Thought (Refutation of Idealism)
iii. Ground of Distinction of Objects into Phenomena and Noumena
iv. Appendix on the Amphiboly of the Concepts of Reflection
(2) Transcendental Dialectic: Transcendental Illusion
a. Paralogisms of Pure Reason
b. Antinomy of Pure Reason
c. Ideal of Pure Reason
d. Appendix to Critique of Speculative Theology
4. Transcendental Doctrine of Method
A. Discipline of Pure Reason
B. Canon of Pure Reason
C. Architectonic of Pure Reason
D. History of Pure Reason

Critique of Pure Reason
Transcendental Doctrine of Elements

First Part: Transcendental Aesthetic
- Space
- Time

Second Part: Transcendental Logic

First Division: Transcendental Analytic
Book I: Analytic of Concepts
- Clue to the discovery of all pure concepts of the understanding
- Deductions of the pure concepts of the understanding

Book II: Analytic of Principles
- Schematism
- System of all principles
- Phenomena and Noumena

Second Division: Transcendental Dialectic
Transcendental Illusion

Pure Reason as the Seat of Transcendental Illusion
Book I: Concept of Pure Reason

Book II: Dialectical Inferences of Pure Reason
Paralogisms (Psychology)
Antinomies (Cosmology)
The Ideal (Theology)

Transcendental Doctrine of Method
- Discipline of Pure Reason
- Canon of Pure Reason
- Architectonic of Pure Reason

History of Pure Reason

I. Transcendental Doctrine of Elements

Transcendental Aesthetic

The Transcendental Aesthetic, as the Critique notes, deals with "all principles of a priori sensibility." As a further delimitation, it "constitutes the first part of the transcendental doctrine of elements, in contrast to that which contains the principles of pure thinking, and is named transcendental logic". In it, what is aimed at is "pure intuition and the mere form of appearances, which is the only thing that sensibility can make available a priori".

It is thus an analytic of the a priori constitution of sensibility; through which "Objects are therefore given to us..., and it alone affords us intuitions". This in itself is an explication of the "pure form of sensible intuitions in general [that] is to be encountered in the mind a priori". Thus, pure form or intuition is the a priori "wherein all of the manifold of appearances is intuited in certain relations" from this, "a science of all principles of a priori sensibility [is called] the transcendental aesthetic". The above stems from the fact that "there are two stems of human cognition...namely sensibility and understanding."

This division, as the critique notes, comes "closer to the language and the sense of the ancients, among whom the division of cognition into αισθητα και νοητα is very well known." An exposition on a priori intuitions is an analysis of the intentional constitution of sensibility. Since this lies a priori in the mind prior to actual object relation; "The transcendental doctrine of the senses will have to belong to the first part of the science of elements, since the conditions under which alone the objects of human cognition are given precede those under which those objects are thought".

Kant distinguishes between the matter and the form of appearances. The matter is "that in the appearance that corresponds to sensation" (A20/B34). The form is "that which so determines the manifold of appearance that it allows of being ordered in certain relations" (A20/B34). Kant's revolutionary claim is that the form of appearances - which he later identifies as space and time - is a contribution made by the faculty of sensation to cognition, rather than something that exists independently of the mind. This is the thrust of Kant's doctrine of the transcendental ideality of space and time.

Kant's arguments for this conclusion are widely debated among Kant scholars. Some see the argument as based on Kant's conclusions that our representation (Vorstellung) of space and time is an a priori intuition. From here Kant is thought to argue that our representation of space and time as a priori intuitions entails that space and time are transcendentally ideal.

It is undeniable from Kant's point of view that in Transcendental Philosophy, the difference of things as they appear and things as they are is a major philosophical discovery. Others see the argument as based upon the question of whether synthetic a priori judgments are possible. Kant is taken to argue that the only way synthetic a priori judgments, such as those made in geometry, are possible is if space is transcendentally ideal.

In Section I (Of Space) of Transcendental Aesthetic in the Critique of Pure Reason Kant poses the following questions: What then are time and space? Are they real existences? Or, are they merely relations or determinations of things, such, however, as would equally belong to these things in themselves, though they should never become objects of intuition; or, are they such as belong only to the form of intuition, and consequently to the subjective constitution of the mind, without which these predicates of time and space could not be attached to any object?

The answer that space and time are real existences belongs to Newton. The answer that space and time are relations or determinations of things even when they are not being sensed belongs to Leibniz. Both answers maintain that space and time exist independently of the subject's awareness. This is exactly what Kant denies in his answer that space and time belong to the subjective constitution of the mind.

Space and Time

Kant gives two expositions of space and time: metaphysical and transcendental. The metaphysical expositions of space and time are concerned with clarifying how those intuitions are known independently of experience. The transcendental expositions purport to show how the metaphysical conclusions give insight into the possibility of already obtained a priori scientific knowledge (A25/B40).

In the transcendental exposition, Kant refers back to his metaphysical exposition in order to show that the sciences would be impossible if space and time were not kinds of pure a priori intuitions. He asks the reader to take the proposition, "two straight lines can neither contain any space nor, consequently, form a figure," and then to try to derive this proposition from the concepts of a straight line and the number two. He concludes that it is simply impossible (A47-48/B65).

Thus, since this information cannot be obtained from analytic reasoning, it must be obtained through synthetic reasoning, i.e., a synthesis of concepts (in this case two and straightness) with the pure (a priori) intuition of space.

In this case, however, it was not experience that furnished the third term; otherwise, the necessary and universal character of geometry would be lost. Only space, which is a pure a priori form of intuition, can make this synthetic judgment, thus it must then be a priori. If geometry does not serve this pure a priori intuition, it is empirical, and would be an experimental science, but geometry does not proceed by measurements—it proceeds by demonstrations.

The other part of the Transcendental Aesthetic argues that time is a pure a priori intuition that renders mathematics possible. Time is not a concept, since otherwise it would merely conform to formal logical analysis (and therefore, to the principle of non-contradiction). However, time makes it possible to deviate from the principle of non-contradiction: indeed, it is possible to say that A and non-A are in the same spatial location if one considers them in different times, and a sufficient alteration between states were to occur (A32/B48). Time and space cannot thus be regarded as existing in themselves. They are a priori forms of sensible intuition.

The current interpretation of Kant states that the subject possesses the capacity to perceive spatial and temporal presentations a priori. The Kantian thesis claims that in order for the subject to have any experience at all, then it must be bounded by these forms of presentations (Vorstellung). Some scholars have offered this position as an example of psychological nativism, as a rebuke to some aspects of classical empiricism.

Kant's thesis concerning the transcendental ideality of space and time limits appearances to the forms of sensibility - indeed, they form the limits within which these appearances can count as sensible; and it necessarily implies that the thing-in-itself is neither limited by them nor can it take the form of an appearance within us apart from the bounds of sensibility (A48-49/B66).

Yet the thing-in-itself is held by Kant to be the cause of that which appears, and this is where an apparent paradox of Kantian critique resides: while we are prohibited from knowledge of the thing-in-itself, we can attribute it as being something beyond ourselves as a causally responsible source of representations within us. Kant's view of space and time rejects both the space and time of Aristotelian physics and the space and time of Newtonian physics.

Transcendental Logic

In the Transcendental Logic, there is a section (titled The Refutation of Idealism) that is intended to free Kant's doctrine from any vestiges of subjective idealism, which would either doubt or deny the existence of external objects (B274-79). Kant's distinction between the appearance and the thing-in-itself is not intended to imply that nothing knowable exists apart from consciousness, as with subjective idealism.

Rather, it declares that knowledge is limited to phenomena as objects of a sensible intuition. In the Fourth Paralogism ("...A Paralogism is a logical fallacy"), Kant further certifies his philosophy as separate from that of subjective idealism by defining his position as a transcendental idealism in accord with empirical realism (A366-80), a form of direct realism. "The Paralogisms of Pure Reason" is the only chapter of the Dialectic that Kant rewrote for the second edition of the Critique of Pure Reason. In the first edition, the Fourth Paralogism offers a defence of transcendental idealism, which Kant reconsidered and relocated in the second edition.

Whereas the Transcendental Aesthetic was concerned with the role of the sensibility, the Transcendental Logic is concerned with the role of the understanding, which Kant defines as the faculty of the mind that deals with concepts. Knowledge, Kant argued, contains two components: intuitions, through which an object is given to us in sensibility, and concepts, through which an object is thought in understanding.

In the Transcendental Aesthetic, he attempted to show that the a priori forms of intuition were space and time, and that these forms were the conditions of all possible intuition. It should therefore be expected that we should find similar a priori concepts in the understanding, and that these pure concepts should be the conditions of all possible thought. The Logic is divided into two parts: the Transcendental Analytic and the Transcendental Dialectic.

The Analytic Kant calls a "logic of truth"; in it he aims to discover these pure concepts which are the conditions of all thought, and are thus what makes knowledge possible. The Transcendental Dialectic Kant calls a "logic of illusion"; in it he aims to expose the illusions that we create when we attempt to apply reason beyond the limits of experience.

The idea of a transcendental logic is that of a logic that gives an account of the origins of our knowledge as well as its relationship to objects. Kant contrasts this with the idea of a general logic, which abstracts from the conditions under which our knowledge is acquired, and from any relation that knowledge has to objects.

According to Helge Svare, "It is important to keep in mind what Kant says here about logic in general, and transcendental logic in particular, being the product of abstraction, so that we are not misled when a few pages later he emphasizes the pure, non-empirical character of the transcendental concepts or the categories."

Kant's investigations in the Transcendental Logic lead him to conclude that understanding and reason can only legitimately be applied to things as they appear phenomenally to us in experience. What things are in themselves as being noumenal, independent of our cognition, remains limited by what is known through phenomenal experience.

First Division: Transcendental Analytic

The Transcendental Analytic is divided into an Analytic of Concepts and an Analytic of Principles, as well as a third section concerned with the distinction between phenomena and noumena. In Chapter III (Of the ground of the division of all objects into phenomena and noumena) of the Transcendental Analytic, Kant generalizes the implications of the Analytic in regard to transcendent objects preparing the way for the explanation in the Transcendental Dialectic about thoughts of transcendent objects, Kant's detailed theory of the content (Inhalt) and origin of our thoughts about specific transcendent objects.

The main sections of the Analytic of Concepts are The Metaphysical Deduction and The Transcendental Deduction of the Categories. The main sections of the Analytic of Principles are the Schematism, Axioms of Intuition, Anticipations of Perception, Analogies of Experience, Postulates and follow the same recurring tabular form:

1. Quantity
2. Quality
3. Relation
4. Modality

In the 2nd edition, these sections are followed by a section titled the Refutation of Idealism.

The Metaphysical Deduction

In the Metaphysical Deduction, Kant aims to derive twelve pure concepts of the understanding (which he calls "categories") from the logical forms of judgment. In the following section, he will go on to argue that these categories are conditions of all thought in general. Kant arranges the forms of judgment in a table of judgments, which he uses to guide the derivation of the table of categories.

The role of the understanding is to make judgments. In judgment, the understanding employs concepts which apply to the intuitions given to us in sensibility. Judgments can take different logical forms, with each form combining concepts in different ways. Kant claims that if we can identify all of the possible logical forms of judgment, this will serve as a "clue" to the discovery of the most basic and general concepts that are employed in making such judgments, and thus that are employed in all thought.

Logicians prior to Kant had concerned themselves to classify the various possible logical forms of judgment. Kant, with only minor modifications, accepts and adopts their work as correct and complete, and lays out all the logical forms of judgment in a table, reduced under four heads:
1. Quantity of Judgments
2. Quality
3. Relation
4. Modality

Under each head, there corresponds three logical forms of judgment:

1. Quantity of Judgments
Universal
Particular
Singular

2. Quality
Affirmative
Negative
Infinite

3. Relation
Categorical
Hypothetical
Disjunctive

4. Modality
Problematic
Assertoric
Apodeictic

This Aristotelian method for classifying judgments is the basis for his own twelve corresponding concepts of the understanding. In deriving these concepts, he reasons roughly as follows. If we are to possess pure concepts of the understanding, they must relate to the logical forms of judgment. However, if these pure concepts are to be applied to intuition, they must have content. But the logical forms of judgment are by themselves abstract and contentless.

Therefore, to determine the pure concepts of the understanding we must identify concepts which both correspond to the logical forms of judgment, and are able to play a role in organising intuition. Kant therefore attempts to extract from each of the logical forms of judgment a concept which relates to intuition. For example, corresponding to the logical form of hypothetical judgment ('If p, then q'), there corresponds the category of causality ('If one event, then another'). Kant calls these pure concepts 'categories', echoing the Aristotelian notion of a category as a concept which is not derived from any more general concept.

He follows a similar method for the other eleven categories, then represents them in the following table:

1. Categories of Quantity
Unity
Plurality
Totality

2. Categories of Quality
Reality
Negation
Limitation

3. Categories of Relation
Inherence and Subsistence (substance and accident)
Causality and Dependence (cause and effect)
Community (reciprocity between agent and patient)

4. Categories of Modality
Possibility - Impossibility
Existence - Non-existence
Necessity - Contingency

These categories, then, are the fundamental, primary, or native concepts of the understanding. These flow from, or constitute the mechanism of understanding and its nature, and are inseparable from its activity. Therefore, for human thought, they are universal and necessary, or a priori. As categories they are not contingent states or images of sensuous consciousness, and hence not to be thence derived. Similarly, they are not known to us independently of such consciousness or of sensible experience.

On the one hand, they are exclusively involved in, and hence come to our knowledge exclusively through, the spontaneous activity of the understanding. This understanding is never active, however, until sensible data are furnished as material for it to act upon, and so it may truly be said that they become known to us "only on the occasion of sensible experience". For Kant, in opposition to Christian Wolff and Thomas Hobbes, the categories exist only in the mind.

These categories are "pure" conceptions of the understanding, in as much as they are independent of all that is contingent in sense. They are not derived from what is called the matter of sense, or from particular, variable sensations. However, they are not independent of the universal and necessary form of sense. Again, Kant, in the "Transcendental Logic", is professedly engaged with the search for an answer to the second main question of the Critique: How is pure physical science, or sensible knowledge, possible?

Kant, now, has said, and, with reference to the kind of knowledge mentioned in the foregoing question, has said truly, that thoughts, without the content which perception supplies, are empty. This is not less true of pure thoughts, than of any others. The content which the pure conceptions, as categories of pure physical science or sensible knowledge, cannot derive from the matter of sense, they must and do derive from its pure form.

And in this relation between the pure conceptions of the understanding and their pure content there is involved, as we shall see, the most intimate community of nature and origin between sense, on its formal side (space and time), and the understanding itself. For Kant, space and time are a priori intuitions. Out of a total of six arguments in favor of space as a priori intuition, Kant presents four of them in the Metaphysical Exposition of space: two argue for space a priori and two for space as intuition.