be another sense of the word "real," in which to assert "A is real" is to assert _less_ than "A is _really_ perceived"--the sense, namely, in which we here assert that the _perception_ of A is real. We find, therefore, that the other class of philosophers were at least right in this: they were right in allowing that the sense in which we commonly say that our perceptions exist is one in which "exist" does not include, even as a part of its meaning, "is perceived." We find that there is a common sense of the word "existence," in which to say "A exists" must mean _less_ than "A is _really_ perceived": since, otherwise, the only possible definition of the word "existence" would be a circular definition. And I may point out that two other definitions, which have been sometimes suggested by philosophers as giving what we commonly mean by "reality" or "existence" are vitiated by the same fault--they also are circular. Some philosophers have sometimes suggested that when we call a thing "real," we mean that it is "systematically connected" in some way with other things. But, when we look into their meaning, we find that what they mean is (what, indeed, is alone plausible)--systematically connected with other _real_ things. And it may possibly be the case that we sometimes use the word "real" in this sense: but, at least, it must be certainly the case, that, if we do, we _also_ use it in another and simpler sense--the sense in which it is employed in the proposed definition. And other philosophers have suggested that what we mean by "real" is--"connected in some way with a purpose--helping or hindering, or the object of a purpose." But if we look into their meaning, we find they mean--connected with a _real_ purpose. And hence, even if we do sometimes mean by "real," "connected with a _real_ purpose," it is plain we also sometimes mean by "real" something simpler than this--that namely, which is meant by "real" in the proposed definition. It is certain, therefore, that we do commonly use the word "existence" in a sense, in which to say "A exists" is _not_ to say "A is perceived," or "A is systematically connected with other real things," or "A is purposive." There is a simpler sense than any of these--the sense in which we say that our own perceptions do exist, and that Sindbad's perceptions did not exist. But when I say this, I am by no means denying that what exists, in this simple sense, may not always _also_ exist in all the others; and that what exists in any of them may not _also_ always exist in this. It is quite possible that what exists is always _also_ perceived, and that what is perceived always _also_ exists. All that I am saying is that, even if this is so, this proposition is significant--is not merely a proposition about the meaning of a word. It is not self-contradictory to suppose that some things which exist are not perceived, and that some things which are perceived do not exist.