The nature of the Platonic view of the world is to be an outlook in which concrete instances, whether they be things, events or situations or whatever, are seen as in the deepest sense parasitic upon what may be called ‘Ideal Contents’, and not as is commonly thought, vice versa. It is, further, a view in which such Ideal Contents form an integrated Order, ranging from Contents of the most generic to the most highly specific, arranged according to affinities, distances and dependencies which spring wholly from what they are, and could not any point be otherwise. All these Ideal Contents and all their ideal relations are such as to reveal themselves perspicuously to a thought which looks for them in the right manner, though they are not in any sense constituted by or for such a thought (Plato: The Written and Unwritten Doctrines, p. 351).
What is essential to the great Platonic revolution is not the erection of predicates into a new sort of logical subjects, though we may seek to express it by doing just this: it is rather the recognition that predicates, senses, universals are the primary stuff, if one may so put it, of experience and reality, that so-called particulars are as such unidentifiable and undiscoverable, their whole being consisting, if one may so phrase it, in instantiating Natures or in having things said of them (Plato: The Written and Unwritten Doctrines, p. 355).