different in every individual of the same family, &c. The idioplasm is the physiological equivalent of this specific individual quality of the sensations and perceptions, and there are reasons analogous with those in favour of the supposition of an idioplasm for the supposition of an individual character amongst animals. The sportsman who has to do with dogs, the trainer with horses, and the keeper with animals will readily admit the existence of this individuality as a constant element. It is clear that we have to do here with something more than a mere rendezvous of perceptions.
But even if this psychical analogue of the idioplasm were proved to exist in the case of animals, it could not be ranked with the intelligible character, the existence of which in any living creature except man cannot be maintained. The intelligible character of men, their individuation, has the same relation to empirical character that memory has to the simple power of recognition. And finally we come to identity, by which the structure, form, law, and cosmos persist even through the change of contents. The considerations from which is drawn the proof of the existence in man of such a noumenal, trans-empirical subject must now be stated briefly. They come from logic and ethics.
Logic deals with the true significance of the principle of identity (also with that of contradiction; the exact relation of these two, and the various modes of stating it are controversial matters outside the present subject). The proposition A = A is axiomatic and self-evident. It is the primitive measure of truth for all other propositions; however much we may think over it we must return to this fundamental proposition. It is the principle of the distinction between truth and error; and he who regards it as meaningless tautology, as was the case with Hegel and many of the later empiricists (this being not the only surprising point of contact between two schools apparently so different) is right in a fashion, but has misunderstood the nature of the proposition. A = A, the principle of all truth, cannot itself be a special truth. He who finds the proposition of identity
