Now, with one class of these philosophers--the class to which, I think, Berkeley belongs--I think I can put myself right comparatively easily. The philosophers I mean are those who say that it is only in the case of one particular class of "contents" (the kind of "content" which Berkeley calls "ideas") that to say "the 'content' A exists" is to say "A is perceived," and who admit that in the case of other contents--myself and my perceptions and thoughts, for example--to say that _these_ exist or are real, is to say of them something different from this. These philosophers admit, that is to say, that the word "exists" has two different senses: and that in only one of these senses is it synonymous with the words "is perceived." When (they hold) I say of such a content as a red patch with gold letters on it that it "exists" I _do_ mean that it is perceived; but when I say of my _perception_ of such a patch that _it_ exists, I do _not_ mean that my perception is perceived but something different from this. Now, it would be nothing strange that one and the same word should be used in two different senses; many words are used in many different senses. But it would, I think, be something very strange indeed, if in the case of a word which we constantly apply to all sorts of different objects, we should uniformly apply it to one large class of object in the one sense and the one sense only and the other large class in the other sense and the other sense only. Usually, in the case of such ambiguous words, it happens that, in different contexts, we apply it to one and the same object in _both_ senses. We sometimes wish to say of a given object that it has the one property, and sometimes we wish to say of the same object that it has the other property; and hence we apply the same word to the same object, at one time in one sense, and at another in the other. I think, therefore, that, even if there were these two different senses of the word "existence," it would be very unlikely that we should not commonly, in some contexts, apply it in the sense, in which (as is alleged) it does apply to perceptions, to "contents" which are not perceptions. Indeed, I think, it is quite plain that we constantly do ask, with regard to what is not a perception, whether _it_ exists, in precisely the same sense, in which we ask, with regard to a perception, whether _it_ exists. We ask in precisely the same sense: Was the Roc a real bird, or merely an imaginary one? and, did Sindbad's perception of the Roc really exist, or is it a fiction that he perceived a Roc? I think, therefore, that the sense in which these philosophers admit that we do apply the word "existence" to perceptions, is one in which we also commonly apply it to "contents" other than perceptions. But, even if this is not the case, I can set myself right with them by a simple explanation. I need merely explain that the sense in which I am proposing to enquire