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

by Norman Kemp Smith

(a) By reflection upon the activity of the mind in the construction of experience, yielding the intuition of a pure manifold; or (b) by reflection upon the space-endowed products ofexperience.[394] The latter mode of reflection may reveal:
	(α) A pure manifold distinct from the manifold of sense; or
	(β) Space as a form of the sensuous manifold.

There are thus three different ways (a, α, β) in which the second view can be developed: (a) represents the view of the Dissertation (1770), of the reply to Eberhard (1790), and of those parts of the first edition’s deduction of the categories which are of very early origin; (α) represents the final standpoint of the Analytic; (β), the prevailing view of the present day, is nowhere accepted by Kant.[395]

Kant’s utterances in the Aesthetic are all of them coloured by the first main view. We can best approach them by way of the contrasted teaching of the Dissertation of 1770. The teaching there formulated practically coincides, as above stated, with (a) of the second main view. Space, he maintains, is neither innate nor acquired from sense-experience.

“Certainly both conceptions [of time and of space] are undoubtedly acquired, not indeed by abstraction from our sensations of objects (for sensation gives the matter, not the form of human cognition), but from the mind’s own action in co-ordinating its sensations in accordance with unchanging laws. Each represents, as it were, an immutable type, and so can be known intuitively. Sensations excite this act of mind but do not contribute to the intuition. There is here nothing innate except this law of the mind according to which it conjoins in a certain manner the sensations derived from the presence of some object.”[396]

How this view is to be reconciled with the contention, no less explicitly maintained,[397] that space is not only a form of intuition but itself a pure intuition, Kant does not make clear. Reflection upon an activity of the mind may yield the representation of space as a form; it is difficult to comprehend how it should also yield an a priori content.

Kant nowhere in the Critique directly discusses the question whether the representation of space is innate or acquired. Such suggestions as occur refer (with the solitary exceptions of A 196 = B 241 and B 166 ff.)[398] only to the categories,[399] or as in the Prolegomena[400] to the Ideas of reason. But in 1790 Kant in his reply to Eberhard[401] again formulates the view of the Dissertation. The Critique allows, he there says, of no innate representations. All, without exception, are acquired. But of certain representations there is an original acquisition (ursprüngliche Erwerbung). Their ground (Grund) is inborn. In the case of space this ground is the mind’s peculiar capacity for acquiring sensations in accordance with its subjective constitution.[402]

“This first formal ground is alone inborn, not the space representation itself. For it always requires impressions to determine the faculty of knowledge to the representation of an object (which in every case is its own action). Thus arises the formal intuition, which we name space, as an originally acquired representation (the form of outer objects in general), the ground of which (as mere receptivity) is likewise inborn, and the acquisition of which long antedates the determinate conception of things which are in accordance with this form.”[403]

That last remark is confusing. Kant cannot mean that the representation of space is acquired prior to sense-experience, but only that since the mind gains it by reflection upon its own activity, it is among the first things to be apprehended—an extremely questionable assertion, could the premisses be granted. If “the determinate conception of things” comes late, still later must come the determinate conception of anything so abstract as pure space. The above passage thus repeats without essential modification the teaching of the Dissertation, and is open to the same objections. This teaching coincides with that of Leibniz in his Nouveaux Essais; and in formulating it in the Dissertation Kant was very probably influenced by Leibniz. Though it is an improvement upon the more extreme forms of the Cartesian doctrine of innate ideas, it does not go sufficiently far.

Now while Kant thus in 1770 and in 1790 so emphatically teaches that the representation of space is not innate, he none the less, in the intermediate period represented by the Aesthetic, would seem to maintain the reactionary view. Space is no mere potential disposition. As a conscious representation it lies ready in the mind. What, then, were the causes which constrained Kant to go back upon his own better views and to adopt so retrograde a position? The answer must be conjectural, but may perhaps be found in the other main point in which the teaching of the Aesthetic is distinguished from that of the Dissertation. Throughout the Critique Kant insists that space is a form of receptivity. It is given to the mind. It has nothing to do with spontaneity or understanding, and therefore cannot be acquired by reflection upon any activity of the mind. But neither can it, as a priori, be acquired from without. Consequently it cannot be acquired at all. But if given, and yet not acquired, it must as a representation lie ready in the mind from the very birth of consciousness. Constrained by such reasoning, Kant views it as given in all its completeness just as truly as is a sensation of colour or sound. This conclusion may not be satisfactory. Kant’s candid recognition of it is, however, greatly preferable to the blurring of the issue by most of his commentators.

Kant came, no doubt, to the more consistent position of the Aesthetic chiefly through further reflection upon the arguments of the Dissertation,[404] and especially by recognition of the fact that though reflection upon an activity of the mind may be regarded as yielding a form of intuition, it can hardly be capable of yielding a pure manifold which can be substituted for, and take the place of, the manifold of sense. There are for Kant only two ways of escape from this unhappy quandary: (a) Either he must return to the Dissertation position, and admit that the mind is active in the construction of space. This he does in the 1790 reply to Eberhard, but only by misrepresenting his own teaching in the Critique. In order consistently to maintain that space is acquired by reflection upon an activity of the mind, he would have to recast the entire Aesthetic, as well as much of the Analytic, and to do so in ways which cannot genuinely harmonise with the main tendencies of his teaching.[405] (b) No such obstacle lay in the way of an alternative modification of his position. Kant might very easily have given up the contention that space is a pure intuition. If he had been willing to recognise that the sole possible manifold of intuition is sensuous, he could then have maintained that though space is innate as a potential form of receptivity, it is acquired only through reflection upon the space-endowed products of sensibility. So obvious are the advantages of this position, so completely does it harmonise with the facts of experience and with the teaching of modern psychology, and so obscure are the various passages in which Kant touches on this central issue, that many of his most competent commentators are prepared to regard it as being the actual teaching of the Critique. The evidence[406] seems to me, however, to refute this interpretation of Kant’s position. The traditional, Cartesian, semi-mystical worship of mathematical truth, as altogether independent of the contingencies of sense-experience, and as a body of knowledge absolutely distinct in origin from the merely empirical sciences, influences Kant’s thinking even at the very moment when he is maintaining, in opposition to the Cartesians, that its subject matter is a merely subjective intuition. Kant, as it would seem, still maintains that there is a pure manifold of intuition distinct from the manifold of sense; and so by the inevitable logic of his thought is constrained to view space as innate in conscious form. This is not, of course, a conclusion which he could permanently stand by, but its elimination would have involved a more radical revision of his whole view of pure intuition and of mathematical science than he was willing to undertake. Though in the Analytic he has come to recognise[407] that it is acquired by reflection upon objects, to the end he would seem to persist in the difficult contention that such reflection yields a pure manifold distinct from the manifold of sense.[408] His belief that mathematical science is based upon pure intuition prevented him from recognising that though space may be a pure form of intuition, it can never by itself constitute a complete intuition. Its sole possible content is the manifold of sense. But even apart from the fact that our apprehension of space is always empirically conditioned, Kant’s view of mathematical propositions as grounded in intuition is, as already observed, not itself tenable. For though intuitions may perhaps be the ultimate subject matter of geometry, concepts are its sole possible instruments. Intuitions yield scientific insight in exact proportion to our powers of restating their complex content in the terms of abstract thought. Until the evidence which they supply has been thus intellectually tested and defined, they cannot be accepted as justifying even the simplest proposition.[409]