A Commentary to Kant's 'Critique of Pure Reason'

by Norman Kemp Smith

Kant begins by drawing a distinction between representing an object absolutely, and representing an object in the Idea.

“In the former case our concepts are employed to determine the object, in the latter case there is in truth only a schema for which no object, not even a hypothetical one, is directly given, and which only enables us to represent to ourselves indirectly other objects in their systematic unity, by means of their relation to this Idea.”[1670]

An Idea is only a schema (Kant in terms of A 655 = B 693 ought rather to have said analogon of a schema) whereby we represent to ourselves, as for instance in the concept of a Highest Intelligence, not an objective reality but only such perfection of Reason as will tend to the greatest possible unity in the empirical employment of understanding.

With this introduction, Kant ushers in his famous “als ob” doctrine. We must view the things of the world as if they derived their existence from a Highest Intelligence. That Idea is heuristic only, not expository. Its purpose is not to enable us to comprehend such a Being, or even to think its existence, but only to show us how we should seek to determine the constitution and connection of the objects of experience. The three transcendental Ideas do not determine an object corresponding to them, but, under the presupposition of such an object in the Idea, lead us to systematic unity of empirical knowledge. When they are thus strictly interpreted as merely regulative of empirical enquiry, they will always endorse experience and never run counter to it. Reason, which seeks completeness of explanation, must therefore always act in accordance with them. Only thereby can experience acquire its fullest possible extension. This is the transcendental deduction of which we are in search. It establishes the indispensableness of the Ideas of Reason for the completion of experience, and their legitimacy as regulative principles.

We may here interrupt Kant’s exposition so far as to point out that this argument does not do justice to the full force of his position. The true Critical contention—and only if we interpret the passage in the light of this contention can the proof be regarded as transcendental in the strict sense—is that the Ideas are necessary to the possibility of each and every experience, involved together with the categories as conditions of the very existence of consciousness. They are not merely regulative, but are regulative of an experience which they also help to make possible.[1671] They express the standards in whose light we condemn all knowledge which does not fulfil them; and we have consequently no option save to endeavour to conform to their demands. In other words, they are not derivative concepts obtained by merely omitting the restrictions essential to our empirical consciousness, but represent a presupposition necessarily involved in all consciousness. Some such restatement of the argument is demanded by the position which Kant has himself outlined in A 645 = B 673 and in A 650 ff. = B 678 ff. Unfortunately he does not return to it. The more sceptical view which he has meantime been developing remains dominant. The deduction is left in this semi-Critical form.

A 672-6 = B 700-4 give a fuller statement of the “als ob” doctrine. In psychology we must proceed as if the mind were a simple substance endowed with personal identity[1672] (in this life at least), not in order to derive explanation of its changing states from the soul so conceived, but to derive them from each other in accordance with the Idea. In cosmology and theology (we may observe the straits to which Kant is reduced in his attempt to distinguish them) we ought to consider all phenomena both in their series and in their totality as if they were due to a highest and all-sufficient unitary ground. In so doing we shall not derive the order and system in the world from the object of the Idea, but only extract from the Idea the rule whereby the understanding attains the greatest possible satisfaction in the connecting of natural causes and effects.

In A 676-7 = B 704-5 Kant resorts to still another distinction—between suppositio relativa and suppositio absoluta. This distinction is suggested by the semi-objectivity of principles that are merely regulative. Though we have to recognise them as necessary, such necessity does not justify the assertion of their independent validity. When we admit a supreme ground as the source of the order and system which the principles demand, we do so only in order to think the universality of the principles with greater definiteness. Such supposition is relative to the needs of Reason in its empirical employment: not absolute, as pointing to the existence of such a being in itself.

“This explains why, in relation to what is given to the senses as existing, we require the Idea of a primordial Being necessary in itself, and yet can never form the slightest concept of it or of its absolute necessity.”[1673]

This last statement leads to the further problem to which Kant here gives his final solution, how if, as has been shown in the Dialectic, the concepts of absolute necessity and of unconditionedness are without meaning, the Ideas of Reason can be entertained at all, even mentally. What is their actual content and how is it possible to conceive them? Kant’s reply is developed in terms of the semi-Critical subjectivist point of view which dominates this section. The Ideas are mere Ideas. They yield not the slightest concept either of the internal possibility or of the necessity of any object corresponding to them. They only seem to do so, owing to a transcendental illusion. On examination we find that the concepts which we employ in thinking them as independently real, are one and all derived from experience. That is to say, we judge of them after the analogy of reality, substance, causality, and necessity in the sensible world.[1674]

”[They are consequently] analoga only of real things, not real things in themselves. We remove from the object of the Idea the conditions which limit the concept of the understanding, but which at the same time alone make it possible for us to have a determinate concept of anything. What we then think is, therefore, a something of which, as it is in itself, we have no concept whatsoever, but which we none the less represent to ourselves as standing in a relation to the sum-total of appearances analogous to that in which appearances stand to one another.”[1675]