2. The Transcendental Analytic.—It is the first problem of the Analytic to attain the pure conceptions of the understanding. Aristotle had already attempted to form a table of these conceptions or categories, but he had collected them empirically instead of deriving them from a common principle, and had numbered among them space and time, though these are no pure conceptions of the understanding, but only forms of intuition. But if we would have a perfect, pure, and regularly arranged table of all the conceptions of the understanding, or all the apriori forms of thought, we must look for a principle out of which we may derive them. This principle is the judgment. The general fundamental conceptions of the understanding may be perfectly attained if we look at all the different modes or forms of the judgment. For this end Kant considers the different kinds of judgment as ordinarily pointed out to us by the science of logic. Now logic shows that there are four kinds of judgment, viz., judgments of

Quantity.Quality.Relation.Modality.
Universal,Affirmative,Categorical,Problematical,
Plurative,Negative,Hypothetical,Assertive,
Singular.Illimitable.Disjunctive.Apodictic.

From these judgments result the same number of fundamental conceptions or categories of the understanding, viz.:

Quantity.Quality.Relation.Modality.
Totality,Reality,Substance and inherence,Possibility and impossibility,
Multiplicity,Negation,Cause and dependence,Being and not-being,
Unity.Limitation.Reciprocal action.Necessity and accidence.

From these twelve categories all the rest may be derived by combination. From the fact that these categories are shown to belong apriori to the understanding, it follows, (1) that these conceptions are apriori, and hence have a necessary and universal validity, (2) that by themselves they are empty forms, and attain a content only through intuitions. But since our intuition is wholly through the sense, these categories have their validity only in their application to the sensuous intuition, which becomes a proper experience only when apprehended in the conceptions of the understanding.—Here we meet a second question; how does this happen? How do objects become subsumed under these forms of the understanding, which for themselves are so empty?

There would be no difficulty with this subsumption if the objects and the conceptions of the understanding were the same in kind. But they are not. Because the objects come to the understanding from the sensory, they are of the nature of the sense. Hence the question arises: how can these sensible objects be subsumed under pure conceptions of the understanding, and fundamental principles (judgments apriori), be formed from them? This cannot result immediately, but there must come in between the two, a third, which must have some thing in common with each, i. e. which is in one respect pure and apriori, and in another sensible. The two pure intuitions of the Transcendental Æsthetics, space and time, especially the latter, are of such a nature. A transcendental time determination, as the determination of coetaneousness, corresponds on the one side to the categories, because it is apriori, and on the other side to the phenomenal objects, because every thing phenomenal can be represented only in time. The transcendental time determination, Kant calls in this respect the transcendental schema, and the use which the understanding makes of it, he calls the transcendental schematism of the pure understanding. The schema is a product of the imaginative faculty, which self-actively determines the inner sense to this, though the schema is something other than a mere image. An image is always merely an individual and determinate intuition, but the schema merely represents the universal process of the imagination, by which it furnishes for a conception a proper image. Hence the schema can only exist in the conception, and never suffers itself to be brought within the sensuous intuition. If, now, we consider more closely the schematism of the understanding, and seek the transcendental time determination for every category, we find that:

(1) Quantity has for a universal schema the series of time or number, which represents the successive addition of one and one of the same kind. I can only represent to myself the pure understanding conception of greatness, except as I bring into the imagination a number of units one after another. If I stop this process at its first beginning, the result is unity; if I let it go on farther I have plurality; and if I suffer it to continue without limit, there is totality. Whenever I meet with objects in the phenomenal world, which I can only apprehend successively, I am directed to apply the conception of greatness, which would not be possible without the schema of the series of time.

(2) Quality has for its schema the content of time. If I wish to represent to myself the understanding conception of reality, which belongs to quality, I bring before me in thought a time filled up, or a content of time. That is real which fills a time. If also I would represent to myself the pure understanding conception of negation, I bring into thought a void time.

(3) The categories of relation take their schemata from the order of time; for if I would represent to myself a determinate relation, I always bring into thought a determinate order of things in time. Substance appears as the persistence of the real in time; causality as regular succession in time; reciprocal action as the regular coetaneousness of the determinations in the one substance, with the determinations in the other.

(4) The categories of modality take their schema from the whole of time, i. e. from whether, and how, an object belongs to time. The schema of possibility is the general harmony of a representation with the conditions of time; the schema of actuality is the existence of an object in a determined time; that of necessity is the existence of an object for all time.