But I said just now that the sensation of blue was analysed into "content" and "existence," and that blue was said to be _the_ content of the idea of blue. There is an ambiguity in this and a possible error, which I must note in passing. The term "content" may be used in two senses. If we use "content" as equivalent to what Mr. Bradley calls the "_what_"--if we mean by it the _whole_ of what is said to exist, when the thing is said to exist, then blue is certainly not _the_ content of the sensation of blue: part of the _content_ of the sensation is, in this sense of the term, that other element which I have called consciousness. The analysis of this sensation into the "content" "blue," on the one hand, and mere existence on the other, is therefore certainly false; in it we have again the self-contradictory identification of "Blue exists" with "The sensation of blue exists," But there is another sense in which "blue" might properly be said to be _the_ content of the sensation--namely, the sense in which "content," like _εἴδος_ is opposed to "substance" or "matter." For the element "consciousness," being common to all sensations, may be and certainly is regarded as in some sense their "substance," and by the "content" of each is only meant that in respect of which one differs from another. In this sense then "blue" might be said to be _the_ content of the sensation; but, in that case, the analysis into "content" and "existence" is, at least, misleading, since under "existence" must be included "_what_ exists" in the sensation other than blue.