This way of proceeding in reference to the actions of others, of which many examples might be given, has a twofold significance in the development of the child; and because of this twofold significance it is one of the most important facts of psychology. Upon it rest, in the opinion of the present writer, correct views of ethics and social philosophy. 1. By such imitation the child learns to associate his own sense of physical power, together with his own private pleasures and pains, with the personal actions which were before observed, it is true, in other persons but not understood. The act of the father has now become his own. So one by one the various attributes which he has found to be characteristic of the persons of his social circle, become his, in his own thought. He is now _for himself_ an agent who has the marks of a Person or a Self. He now understands _from_ _the inside_ all the various personal suggestions. What he saw persons do is now no longer "projective"--simply there, outside, in the environment; it has become what we call "subjective." The details are grouped and held together by the sense of agency working itself out in his imitative struggles. This is what we mean by Self-consciousness. It is not an inborn thing with the child. He gradually acquires it. And it is not a sense of a distinct and separate self, first known and then compared with other persons. On the contrary, it is gradually built up in the child's mind from the same material exactly as that of which he makes up his thought of other persons. The deeds he can do he first sees others doing; only then can he imitate them and find out that he also is a being who can perform them. So it goes all through our lives. Our sense of Self is constantly changing, constantly being enriched. We have not the same thought of self two days in succession. To-day I think of myself as something to be proud of, to-morrow as something to be ashamed of. To-day I learn something from you, and the thought that it is common to you and to me is the basis of my sympathy with you. To-morrow I learn to commit the unworthy act which Mr. A. commits, and the thought that he and I are so far the same is the basis of the common disapproval which I feel of him and me.