I pass on now to the main task of the present chapter - the examination of some of the more formidable criticisms which have been levelled against the doctrine of the 'supra-rational' Reality. These criticisms may be conveniently grouped for purposes of discussion into two classes. There are, in the first place, the indirect criticisms which emanate from the counter-assertion that the primary certitude of all philosophy is that 'the real is the rational,' and that the business of philosophy consists not in debating a principle whose certainty may be apodeictically demonstrated, but rather in tracing its application to the various spheres of experience. And secondly, there are the direct criticisms which take up the notion of a 'supra-rational' Reality and profess to find in it a manifest self-contradiction. I shall deal with the former of these classes in the present section.
I need hardly say that the teaching which I have in mind here is that of the post-Kantian development of Idealism. It must have impressed itself upon all who are familiar with this body of thought how profound and relatively untroubled is the confidence of its exponents that at last philosophy has laid hold of the principle which is the one authentic key to the solution of all problems. However difficult may be its application in detail (and Idealists have not as a rule disguised that difficulty), still this principle - the 'Identity of Thought and Reality,' or the 'Rationality of the Real' - is absolutely compelled, so it is maintained, upon anyone who has understood the reorientation of the metaphysical problem which is necessitated by Kant's own development of it. Kant's postulation of an unknowable 'noumenal' reality behind the phenomena is based ultimately, it is held, upon a defective logic inherited from his Rationalist precursors. When we correct this logic, reinterpreting in terms of the true view of the nature and function of thought, the inference to the philosophy of Absolute Idealism is, it is claimed, irresistible.
What I want to suggest here is that the supposed necessity of the transition 'from Kant to Hegel' rests upon a fundamental fallacy : that while Idealism has been entirely in the right in insisting upon the revision of what it takes to be the Kantian view of 'pure thought,' it has gone hopelessly astray in supposing that the metaphysical corollary of this revision is the doctrine of the identity of Thought and Reality, and the consequent repudiation of the 'noumenal'.
Let me in a few words remind the reader of the substance of the Idealist's reinterpretation of the Kantian distinction of the noumenal from the phenomenal, as one finds it, for example, in Edward Caird's great work on Kant.
Influenced by his Rationalist upbringing, and by his unwavering faith in the infallibility of the traditional or formal logic, Kant developed his philosophy (it is maintained) on the assumption that 'pure' thought is an analytic unity, whose principle is bare self-identity. The ideal form of truth is 'A is A.' The mind cannot accept as theoretically satisfying, and as therefore adequately expressive of reality, any content which is not resoluble into this form. But if this be the ideal which thought demands, it is obvious that in the synthetic operations of the 'understanding' the mind is immersed in a process which never can lead to theoretical satisfaction or truth. That process may be necessary : it may be, as for Kant, the one way in which the mind can deal with the 'given manifold' which confronts it. If so, it will have a logic of its own which it will be imperative to study. But it will be an imperfect logic in that it deals with an imperfect expression of thought, a departure of thought from the purity of its inherent ideal. The syntheses of the understanding, then, can never produce truth. And the world which they reveal is one which, however systematically and elaborately presented, cannot be accepted by thought as the 'real' world. We must pronounce it to be a merely 'phenomenal' world, an appearance of that real world which the demand of thought posits but which remains ever impervious to the best efforts of thought to understand it. Reality, or the noumenal, is, at least theoretically, 'unknowable.' But, the Idealist rejoins, this supposed gulf between the real world and the world disclosed by the understanding rests upon the doctrine that thought is an analytic unity,1 and this doctrine is manifestly false. It is not merely in organising the world of sense experience that thought is unable to adopt the principle of bare self-identity. It never does, and never can, adopt it. For A is A - or that from which it ultimately derives, the 'I am I' which, Kant believes, expresses the unity of self-consciousness - shows itself on reflection not to stand for any movement of thought at all, but to be strictly meaningless. Differences are just as necessary to thinking as unity is. The principle which inspires thought is, we must say, not abstract identity, but identity in difference. Thought, in short, is essentially a synthetic unity. And once we have seen this, there is no longer any ground for supposing that the syntheses of the understanding are alien to thought's pure nature. On the contrary, they appear now as the advancing expression of thought's effort to realise adequately its own principle, identity or unity in difference. The consummation arrived at in the progress of the understanding, systematic unity of differences, is also the positive realisation of thought's own nature. Thus the articulation of an objective world and the articulation of thought's own nature proceed pari passu. The 'world' of the understanding is, accordingly, the revelation of truth and reality. We must still say, indeed, that in so far as thought's ideal is only imperfectly realised in this world, the real has not revealed itself in its final character. But interpreting the ideal of thought now as 'identity in difference,' we must see in the activity of the understanding the onward march of truth, and must substitute for the 'phenomenal' world of Kant a world in which ultimate reality progressively manifests itself according to the degree in which the ideal of 'system' or 'unity in difference' finds expression.
1 The reader will remember that I am here only expounding - not defending - what I take to be Caird's interpretation of Kant. The accuracy of that interpretation is not at present in question.