But this was a digression. The point I had established so far was that in every sensation or idea we must distinguish two elements, (1) the "object," or that in which one differs from another; and (2) "consciousness," or that which all have in common--that which makes them sensations or mental facts. This being so, it followed that when a sensation or idea exists, we have to choose between the alternatives that either object alone, or consciousness alone, or both, exist; and I showed that of these alternatives one, namely that the object only exists, is excluded by the fact that what we mean to assert is certainly the existence of a mental fact. There remains the question: Do both exist? Or does the consciousness alone? And to this question one answer has hitherto been given universally: That both exist.
This answer follows from the analysis hitherto accepted of the relation of what I have called "object" to "consciousness" in any sensation or idea. It is held that what I call the object is merely the "content" of a sensation or idea. It is held that in each case we can distinguish two elements and two only, (1) the fact that there is feeling or experience, and (2) _what_ is felt or experienced; the sensation or idea, it is said, forms a whole, in which we must distinguish two "inseparable aspects," "content" and "existence." I shall try to show that this analysis is false; and for that purpose I must ask what may seem an extraordinary question: namely what is meant by saying that one thing is "content" of another? It is not usual to ask this question; the term is used as if everybody must understand it. But since I am going to maintain that "blue" is _not_ the content of the sensation of blue, and what is more important, that, even if it were this analysis would leave out the most important element in the sensation of blue, it is necessary that I should try to explain precisely what it is that I shall deny.
What then is meant by saying that one thing is the "content" of another? First of all I wish to point out that "blue" is rightly and properly said to be part of the content of a blue flower. If, therefore, we also assert that it is part of the content of the sensation of blue, we assert that it has to the other parts (if any) of this whole the same relation which it has to the other parts of a blue flower--and we assert only this: we cannot mean to assert that it has to the sensation of blue any relation which it does not have to the blue flower. And we have seen that the sensation of blue contains at least one other element beside blue--namely, what I call "consciousness," which makes it a sensation. So far then as we assert that blue is the content of the sensation, we assert that it has to this "consciousness" the same relation which it has to the other parts of a blue flower: we do assert this, and we assert no more than this. Into the question what exactly the relation is between blue and a blue flower in virtue of which we call the former part of its "content" I do not propose to enter. It is sufficient for my purpose to point out that it is the general relation most commonly meant when we talk of a thing and its qualities; and that this relation is such that to say the thing exists implies that the qualities also exist. The _content_ of the thing is _what_ we assert to exist, when we assert _that_ the thing exists.