But Kant does not himself recognise any conflict between this teaching and the doctrine of the Aesthetic. He seems to himself merely to be making more definite a position which he has consistently held all along; and this was possible owing to his retention and more efficient formulation of the second of the two distinctions mentioned above, viz. that between the manifold of sense and the manifold of intuition. This distinction enables him to graft the new view upon the old, and so in the very act of insisting upon the indispensableness of the conceptual syntheses of understanding, none the less to maintain his view of geometry as an intuitive science.[414]
“Space and time contain a manifold of pure a priori intuition, but at the same time are conditions of the receptivity of our mind—conditions under which alone it can receive representations of objects, and which therefore must also affect the concept of them. But if this manifold is to be known, the spontaneity of our thinking requires that it be gone through in a certain way, taken up, and connected. This action I name synthesis.... Such a synthesis is pure, if the manifold is not empirical, but is given a priori, as is that of space and of time.”[415]
Thus Kant recognises that space, as apprehended by us, is constructed, not given, and so by implication that the infinitude of space is a principle of apprehension, not a given intuition. But he also holds to the view that it contains a pure, and presumably infinite, manifold, given as such.[416] In what this pure manifold consists, and how the description of it as a manifold, demanding synthesis for its apprehension, is to be reconciled with its continuity, Kant nowhere even attempts to explain. Nor does he show what the simple elements are from which the synthesis of apprehension and reproduction in pure intuition might start. The unity and multiplicity of space are, indeed, as he himself recognises,[417] inseparably involved in one another; and recognition of this fact must render it extremely difficult to assign them to separate faculties. For the same reason it is impossible to distinguish temporally, as Kant so frequently does, the processes of synthesis and of analysis, making the former in all cases precede the latter in time. The very nature of space and time, and, as he came to recognise, the very nature of all Ideas of reason, in so far as they involve the notion of the unconditioned, conflict with such a view.
Even when Kant is dealing with space as a principle of synthesis, he speaks with no very certain voice. In the Analytic it is ascribed to the co-operation of sensibility and understanding. In the Dialectic it is, by implication, ascribed to Reason; and in the Metaphysical First Principles it is explicitly so ascribed.
“Absolute space cannot be object of experience; for space without matter is no object of perception, and yet it is a necessary conception of Reason, and therefore nothing but a mere Idea.”[418] “Absolute space is not necessary as a conception of an actual object, but as an Idea which can serve as rule....”[419]
Kant’s teaching in the Critique of Judgment is a further development of this position.
“The mind listens to the voice of Reason which, for every given magnitude—even for those that can never be entirely apprehended, although (in sensible representation) they are judged as entirely given—requires totality.... It does not even except the infinite (space and past time) from this requirement; on the contrary, it renders it unavoidable to think the infinite (in the judgment of common reason) as entirely given (in its totality). But the infinite is absolutely (not merely comparatively) great. Compared with it everything else (of the same kind of magnitudes) is small. But what is most important is that the mere ability to think it as a whole indicates a faculty of mind which surpasses every standard of sense.... The bare capability of thinking the given infinite without contradiction requires in the human mind a faculty itself supersensible. For it is only by means of this faculty and its Idea of a noumenon ... that the infinite of the world of sense, in the pure intellectual estimation of magnitude, can be completely comprehended under one concept.... Nature is, therefore, sublime in those of its phenomena, whose intuition brings with it the Idea of its infinity.... For just as imagination and understanding, in judging of the beautiful, generate a subjective purposiveness of the mental powers by means of their harmony, so imagination and Reason do so by means of their conflict.”[420]
Kant has here departed very far indeed from the position of the Aesthetic.[421]