The principle of psychology recognised above under the phrase Kinaesthetic Equivalents, teaches us that the idea of a movement, coming into the mind through sight or some other sense, stirs up the proper apparatus to bring about the same movement in the observer.

This we see in the common tendency of an audience to repeat the gestures of a speaker, and in many similar cases.

When this principle is extended to include all sorts of experiences besides those of movement, we have what is generally called Imitation.

Moreover, every time that by action the child imitates, he perceives his own imitation, and this again acts as a "copy" or model for another repetition of the act, and so on.

This method of keeping himself going gives the young animal or child constant practice, and renders him more and more efficient in the acts necessary to his life.
6.