that throughout its history it was always such that no other object could occupy its place, whatever that place might be, at the same time with this impenetrable individual. Thus the individual would remain always unique, by virtue of its permanent exclusion of any other from the place occupied by it at any time. Hence the conceived uniqueness of the individual gets defined. It is admitted by Wundt, and by others, that such impenetrability and continuity is only imperfectly observable in our actual experience of things; and this is why, according to Wundt, the conception of the ordinary thing of common-sense gradually gives place, as science progresses, to the conception of ideal things, called substances, whereof molecules, atoms, etc., are examples. But the origin and essential nature of the concept of the individual is supposed to be thus explained.
To this familiar explanation of individuality we must still stubbornly reply, that what it has identified is always a collection of universal types, never an individual. In the visual space before me at any time, I actually see — what? So far, masses of colour. What, from a logical point of view, are these? Answer, universals. Were I confined to visual experience, I should in the long run, and after allowing for the occasional occultation or eclipse of one visible object by another, learn that these same masses of colour are mutually exclusive, so far as concerns the occupation of the same space at any time. But would this knowledge, viewed simply in itself, apart from other facts and motives, be what I now call a knowledge of individual things? Answer,
