unless it is acted on by some other external force, when both the external body and the stone itself will have their paths changed; but the animal body may pass from the hill to the valley and back again by its own initiative, not that it can add energy to itself or subtract energy from itself; it cannot create or annihilate motion, but it can direct this motion in a path at will; it can pursue the path of its own choice. All this has been set forth fully in the former work.
All activities are controlled by motives, and the motive for sport is pleasure; but it is a pleasure of a particular kind—it is a pleasure in physical activity. Now, we must notice that it is the pleasure of the body whose structure and metabolism are inherited from its ancestors; hence it must be some kind of an activity consistent with the inherited structure. So far, then, the activity is fixed by inheritance, but within these fixed limits there is still great variety of activities from which to choose. What activity will the infant choose? Manifestly it will choose that activity which is suggested by its acts of psychosis as they are developed immediately after birth, and perhaps to some extent from prenatal activities which we may not here stop to consider. The first activities which the infant animal observes, if he belongs to any of the higher groups, is the activity of parents. Thus, the infant child makes judgments about parental activities, and by the law of genesis first strives to engage in the activities which it sees in the parents. Having supplied its wants for food, this food itself produces metabolic processes which ramify through its organ in excess of the amount necessary for digestion. With its inheritance of organization and superabundance of metabolic activity, it is ready to engage in other activities which are first taught by the parent as activities of nurture, and the infant is thus led to engage in mimetic activities. Connate with these are the activities of metabolism itself, the seizing, swallowing, and digestion of food; but the additional activities in which it engages are mimetic. Hence it is that a long succession of great scholars
