Athletes and actors—let actors stand for the set of performing artists—share much. They share the need to make gesture as fluid and economical as possible, to make out of a welter of choices the single, precisely right one. They share the need for impeccable and split-second timing. They share the need for thousands of hours of practice in order to train the body to become the perfect, instinctive instrument to express. Both athlete and actor, out of that congeries of emotion, choice, strategy, knowledge of terrain, mood of spectators, condition of spectators in the ensemble, secret awareness of injury or weakness, and as nearly an absolute concentration as possible so that all externalities are integrated, all distraction absorbed to the self, must be able to change the self so successfully that it changes us.