Immanuel Kant's Critique of Pure Reason — trans. F. Max Müller

thing is given, a concept also of the object, which is given in intuition as a phenomenon. Such concepts of objects in general therefore must form conditions a priori of all knowledge produced by experience, and the objective validity of the categories, as being such concepts a prioi'i, rests on this very fact that by them alone, so far as the form of thought is concerned, experience becomes possible. If by them only it is possible to think any object of experience, it follows that they refer by necessity and a priori to all objects of experience.

There is therefore a principle for the trans- [p. 94] cendental deduction of all concepts a priori which must guide the whole of our investigation, namely, that all must be recognized as conditions a priori of the possibility of experience, whether of intuition, which is found in it, or of thought. Concepts which supply the objective ground of the possibility of experience are for that very reason necessary. An analysis of the experience in which they are found would not be a deduction, but a mere illustration, because they would there have an accidental character only. Nay, without their original relation to all possible experience in which objects of knowledge occur, their relation to any single object would be quite incomprehensible.

[There are three original sources, or call them faculties or powers of the soul, which contain the conditions of the possibility of all experience, and which themselves cannot be derived from any other faculty, namely, sense, imagination, and apperception. On them is founded —

1. The synopsis of the manifold a priori through the senses.

2. The synthesis of this manifold through the imagination.

Transcendental Analytic 79

3. The unity of that synthesis by means of original apperception. ,

Besides their empirical use all these faculties have a transcendental use also, referring to the form only and possible a priori. With regard to the senses we have discussed that transcendental use in the first part, [p. 95] and we shall now proceed to an investigation of the remaining two, according to their true nature.^]

DEDUCTION OF THE PURE CONCEPTS OF THE UNDERSTANDING

Section II Of the a priori Grounds for the Possibility of Experience

[That a concept should be produced entirely a priori and yet refer to an object, though itself neither belonging to the sphere of possible experience, nor consisting of the elements of such an experience, is self-contradictory and impossible. It would have no contents, because no intuition corresponds to it, and intuitions by which objects are given to us constitute the whole field or the complete object of possible experience. An <? /r/^r? concept therefore not referring to experience would be the logical form only of a concept, but not the concept itself by which something is thought.

If therefore there exist any pure concepts a priori^ though they cannot contain anything empirical, they must nevertheless all be conditions a priori of a possible experience, on which alone their objective reality depends.

^ The last paragraph is omitted in the Second Edition. There is instead a criticism of Locke and Hume, Supplement XIII. The Deduction of the Categories is much changed, as seen in Supplement XIV.

8o Transceiidejital Analytic

If therefore we wish to know how pure concepts of the understanding are possible, we must try to find out what are the conditions a priori on which the possibihty [p. 96] of experience depends, nay, on which it is founded, apart from all that is empirical in phenomena. A concept expressing this formal and objective condition of experience with sufficient generality might properly be called a pure concept of the understanding. If we once have these pure concepts of the understanding, we may also imagine objects which are either impossible, or, if not impossible in themselves, yet can never be given in any experience. We have only in the connection of those concepts to leave out something which necessarily belongs to the conditions of a possible experience (concept of a spirit), or to extend pure concepts of the understanding beyond what can be reached by experience (concept of God). But the elements of all knowledge a priori, even of gratuitous and preposterous fancies, though not borrowed from experience (for in that case they would not be knowledge a priori) must nevertheless contain the pure conditions a priori of a possible experience and its object, otherwise not only would nothing be thought by them, but they themselves, being without data, could never arise in our mind.

Such concepts, then, which comprehend the pure thinking a priori involved in every experience, are discovered in the categories, and it is really a sufficient deduction of them and a justification of their objective validity, if we succeed in proving that by them alone an object [p. 97] can be thought. But as in such a process of thinking more is at work than the faculty of thinking only, namely, the understanding, and as the understanding, as a faculty

Transcendental Analytic 8i