participants (they being usually of the same species) accompanies the signal with appropriate movements. I permit myself no judgment of the value of this hypothesis, but I believe its adequacy to meet the case is incontrovertible. Bain, too, in the fourth edition of his work cited above, has made a suggestion looking in the same direction, by which the use of the word instinct gains a certain justification. Nor should it be forgotten that to strengthen this “readiness” a whole series of other requirements may be present, which for convenience in this analysis I may call instinctive. Perhaps an illustration of a movement concept which is not imitative in the ordinary sense will make this clear. If we think intentionally and definitely of the movements involved in whistling, we are likely to feel a mild inclination to whistle, which, however, is commonly easy enough to overcome. Therefore we call it a certain “readiness” in preference to a stronger term, such as “impulse.” But let this mental process take place in church during service; the corresponding action, it is true, is not performed, because of the influence of contrary motives, but the impulse may nevertheless be so strong that their subject suffers great annoyance. Why is this? Probably because the idea of not whistling excites the instinctive impulse toward activity of the movement apparatus (experimentation) as well as the fighting instinct,[538] which resents such constraint and lends itself as a powerful auxiliary to the movement impulse. It is just in this way that the perception of movement made by another arouses special instinctive emotions, and illustrates the power of the imitative impulse. This, then, is a brief explanation of the grounds of the theory developed above, according to which imitation serves as a complement to instincts which have been weakened in favour of intellectual development or are, for whatever reason, inadequate to the individual’s life tasks.