Locke's account of the way in which we get the idea, and of its nature, is as follows: "All the ideas of all the sensible qualities of a cherry come into my mind by sensation. The ideas of these qualities and actions, or powers, are perceived by the mind to be by themselves inconsistent with existence. They cannot subsist of themselves. Hence the mind perceives their necessary connection with inherence, or with being supported." Correlative to the idea of being supported is, of course, the idea of the support. But this idea "is not represented to the mind by any clear and distinct idea; the obscure and vague, indistinct idea of thing or something, is all that is left." Or yet more simply, "Taking notice that a certain number of simple ideas go together, and not imagining how these simple ideas can subsist by themselves, we accustom ourselves to suppose some substratum wherein they do subsist, and from which they do result." Hence the only idea we have of it is of something which underlies known qualities. It is their "supposed, but unknown, support." If we translate these expressions into the ideas of to-day, we see that they are equivalent to the view of the world which is given us by scientific categories when these categories are regarded not merely as scientific, but also as philosophic; that is, capable of interpreting and expressing the ultimate nature of experience. This modern view uses the words "things-in-themselves" (or absolute realities) and "phenomena." It says that we know nothing of existence as it is in itself, but only of its phenomena. Mind, matter, objects, are all substances, all equally substances, and all have their unknown essence and their phenomenal appearance. Such a distinction between the known and the unknown can rest, it is evident, only upon a separation between reality and phenomena similar to that which Locke makes between substance and qualities. In knowing the latter, we know nothing of the former. Although the latter are called "phenomena," they do not really manifest the substantial reality; they conceal it. This absolute distinction between substance and quality, between reality and phenomenon, rests, in turn, upon the hypothesis that reality is _mere_ existence; that is, it is something which is, and that is all. It is a substratum; it lies under, in a passive way, qualities; it is (literally) substance; it simply stands, inactively, under phenomena. It may, by possibility, _have_ actions; but it _has_ them. Activities are qualities which, like all qualities, are in external relation to the substance. Being, in other words, is the primary notion, and "being" means something essentially passive and merely enduring, accidentally and secondarily something acting. Here, as elsewhere, Locke is the father of the mechanical philosophy of to-day.