rest, now of this faculty and now of that, as permits the bringing of it up to a state of high efficiency by the repair which follows waste. . . . Every one of the mental powers, then, being subject to this law, that its organ when dormant for an interval longer than ordinary becomes unusually ready to act—unusually ready to have its correlative feelings aroused, giving an unusual readiness to enter upon all the correlative activities; it happens that a simulation of those activities is easily fallen into, when circumstances offer it, in place of the real activities. Hence play of all kinds—hence this tendency to superfluous and useless exercise of faculties that have been quiescent," for the mere pleasure that attends this exercise. He goes on to say: "A cat, with claws and appended muscles adjusted to daily action in catching prey, but now leading a life that is but in a small degree predatory, has a craving to exercise these parts; and may be seen to satisfy the craving by stretching out her legs, protruding her claws, and pulling at some such surface as the covering of a chair or the bark of a tree. . . . This useless activity of unused organs, which in such cases hardly rises to what we call play, passes into play ordinarily so called where there is a more manifest union of feeling with the action. Play is equally an artificial exercise of powers which, in default of their natural exercise, become so ready to discharge that they relieve themselves by simulated actions in place of real actions. For dogs and other predatory creatures show us unmistakably that their play consists of mimic chase and mimic fighting—they pursue one another, they try to overthrow one another, they bite one another as much as they dare. And so with the kitten running after a cotton ball, making it roll and again catching it, crouching as though in ambush and then leaping on it, we see that the whole sport is a dramatizing of the pursuit of prey—an ideal satisfaction for the destructive instincts in the absence of real satisfaction for them." The plays of children carry these low beginnings to a higher state. Spencer thinks that gratification from a victory at chess is a substitute for ruder victories of an earlier time. The banter of a playful conversation is also a mimic battle, in which words take the place of coarser weapons.
It would be absurd, of course, to pretend that such play is in any sense fine art, but we may see in it the impulse that sets the faculties in motion for the highest artistic productions. This we shall presently undertake to illustrate in tracing the development of the arts. As a preliminary to this, we may note the marks of differentiation which distinguish the arts of pleasure from the arts of life: 1. The practice of the useful arts is accompanied by a sense of necessity, growing out of the constant feeling that the process is a serious one. That of the arts of pleasure is attended with a sense of freedom, resulting from the surcharge of energy