He has a suggestion to make in every emergency, a line of conduct for each of his company, all marked out or supplied on the spur of the moment by his own quick sense of appropriate action; and for him, as for no one else, to hesitate is to be lost.
Now what this general policy or method of growth means to his consciousness is becoming more and more clear in the light of the theory of mental types.

The reason a person is motor is that his mind tends always to be filled up most easily with memories or revived images of the twitchings, tensions, contractions, expansions, of the activities of the muscular system.

He is a motor because the means of his thought generally, the mental coins which pass current in his thought exchange, are muscular sensations or the traces which such sensations have left in his memory.

The very means by which he thinks of a situation, an event, a duty, is not the way it looked, or the way it sounded, or the way it smelt, tasted, or felt to the touch--in any of the experiences to which these senses are involved--but the means, the representatives, the instruments of his thought, are the feelings of the way he has acted.

He has a tendency--and he comes to have it more and more--to get a muscular representation of everything; and his gauge of the value of this or that is this muscular measure of it, in terms of the action which it is calculated to draw out.
It is then this preference for one particular kind of mental imagery, and that the motor, or muscular kind, which gives this type of child his peculiarity in this more psychological period.