a much more complicated and extraordinary one. This new and anomalous phenomenon which accompanies our sensations, but which is, at the same time, completely distinct from them, is the fact of our own personality, the fact and the notion denoted by the word "I." Surely no one will maintain that this realisation of self, in conjunction with our sensations, and as distinguished from the objects causing them, is the same fact as these sensations themselves. In man, then, there is the notion and the reality of himself, as well as the sensation that passes through him. In other words, he is not only sentient, like other animals, but, unlike them, he is sentient with a consciousness, or reference to self, of sensation; two very different, and, as we have already seen, and shall see still further, mutually repugnant and antithetical states of existence.
This consciousness of sensation, then, is the other fact contained in perception; and it is an inquiry into the nature and origin of this fact, and of it alone, that forms the true and proper problem of psychology when we are busied with the phenomena of perception; because it is this fact, and not the fact of sensation, which constitutes man's peculiar and distinctive characteristic, and lies as the foundation-stone of all the grander structures of his moral and intellectual being.
We now then ask: Have Dr Brown and other philosophers entertained the problem as to the origin and import of this fact—the fact, namely, of con-
