I know a that, in the ordinary sense of the word see I am really seeing two coins; an assertion which includes, if it is not identical with, the assertion that the visual experiences, which consist in my direct apprehension of those two elliptical patches of colour, are sensations proper, and are not either hallucinations nor mere experiences of images that the upper sides of the coins are really approximately circular, and not merely elliptical like the visual sensibles; that the coins have another side, and an inside, though I don't see it; that the upper side of the half crown is really larger than that of the florin, though its visual sensible is smaller than the visual sensible of the upper side of the florin: that both coins continue to exist, even when I turn away my head or shut my eyes; but in saying this, I do not, of course, mean to say that there is absolutely no change in them; I daresay there must be some change, and I do not know how to define exactly what I do mean.