the answer is the further question, how can that be knowledge even in its most elementary phase--the phase of the reception of simple ideas --which is not a capacity of distinction between real and apparent, between true and false? If its beginning is a mode of consciousness, such as mere sensation would be--which, because excluding all reference, excludes that reference of itself to something else without which there could be no consciousness of a distinction between an ‘is’ and an ‘is not,’ and therefore no true judgment at all--how can any repetition of such modes give such a judgment? [1] [1] Cf. the ground of distinction between clearness and obscurity of ideas; (Book II. chap. xxix. sec. 2) ‘Our simple ideas are clear when they are such as the objects themselves, whence they are taken, did or might in a well-ordered sensation or perception, present them.’ As Locke always assumes that immediate consciousness can tell whether an idea is clear or not, it follows that immediate consciousness must tell of ‘the object itself, whence the idea is taken.’ It involves a judgment in which mind and thing are distinguished. 24. The fact is that the ‘simple idea’ with Locke, as the beginning of knowledge, is already, at its minimum, the judgment, ‘I have an idea different from other ideas, which I did not make for myself.’ His confusion of this judgment with sensation is merely the fundamental confusion, on which all empirical psychology rests, between two essentially distinct questions--one metaphysical, What is the simplest element of knowledge? the other physiological, What are the conditions in the individual human organism in virtue of which it becomes a vehicle of knowledge? Though he failed, however, to distinguish these questions, their difference made itself appear in a certain divergence between the second and fourth books of his Essay. So far we have limited our consideration to passages in the second book, in which he treats _eo nomine_ of ideas; of simple ideas as the original of knowledge, of complex ones as formed in its process. Here the physical theory is predominant. The beginning of knowledge is that without which the animal is incapable of it, viz. sensation regarded as an impression through ‘animal spirits’ on the brain. But it can only be so represented because sensation is identified with that which later psychology distinguished from it as Perception, and for which no physical theory can account. As we have seen, the whole theory of this (the second) book turns upon the supposition that the simple idea of sensation is in every case an idea of a sensible quality, and that it is so, not merely for us, considering it _ex parte post_, but consciously for the individual subject, which can mean nothing else than that it distinguishes itself from, and refers itself to, a thing. Locke himself, indeed, according to his plan of bringing in a ‘faculty of the mind’ whenever it is convenient, would