But what sort of a thing can this "source" be?
One kind of view, which I think is very commonly held, is that it is something "spiritual" in its nature, or something whose nature is utterly unknown to us. And those who hold this view are apt to add, that it is not really "circular," in any sense at all; nor is the "source" of my half-crown experience, in any sense at all, "bigger" than that of my florin experience. But if this addition were seriously meant, it would, of course, amount to saying that propositions (_b_) and (_d_) are not true, in any sense at all; and I do not think that those who make it, really mean to say this. I think that what they mean is only that the only sense in which those "sources" are circular, and one bigger than the other, is one in which to say this merely amounts to saying that the sensibles, which they _would_ cause us to experience, under certain conditions, _would_ be circular, and one bigger than the other. In other words, in order to give a true interpretation to the propositions that the coins are circular and one bigger than the other, they say that we must interpret them in the same kind of way in which view (1) interpreted them; and the only difference between their view and view (1), is that, whereas _that_ said that you must give a Pickwickian interpretation _both_ to the assertion that the coins _exist, and_ to the assertion that they are _circular_, they say that you must _not_ give it to the former assertion, and must to the latter.
To this view my objection is only that any reason there may be for saying that the "sources" exist in other than a Pickwickian sense, seems to me to be also a reason for saying that they are "circular" in a sense that is not Pickwickian. I have just as strong a propensity to believe that they are really circular, in a simple and natural sense, as that they exist in such a sense: and I know of no better reason for believing either.
(3) It may be suggested, next, that these "sources," instead of being something spiritual in their nature or something of a nature utterly unknown, consist simply of sensibles, of a kind which I have previously tried to define; namely of all those sensibles, which anybody _would,_ under the actual physical conditions, experience in _sensations proper_ of which the half-crown and the florin were the source, _if_ their bodies were in any of the positions relatively to those coins, in which they would get sensations from them at all. We saw before that it seems _possible_ that all these sensibles do really exist at times when they are not experienced, and that some people, at all events, seem to have a strong propensity to believe that they do. And in favour of the view that some such huge collection of sensibles _is_ the upper side of the half-crown, is the fact that we do seem to have a strong propensity to believe that any particular sensible, which we directly apprehend in looking at the upper side of the half-crown, and of our direct apprehension of which the upper side is the source, is _in the place_ in which the upper side is. And that _some_ sense might be given to the expression "in the same place as," in which it could be true that sensibles of all sorts of different shapes and sizes, and of all sorts of different colours, were in the same place at the same time, seems to me to be possible. But the objection to this view seems to me to be the same as to the last; namely that if the upper side of the half-crown were identical with such a collection of sensibles, then the only sense in which it could be said to be "circular," or bigger than that of the florin, would certainly be very Pickwickian, though not the same as on that view.