It is not necessary here to discuss the nature of instinct, to distinguish between an instinct and a more general inborn tendency, or to attempt a complete list of the instincts and inborn tendencies of man. Nor need I ask whether every choice made by a human being can be traced, directly or indirectly, to one or more of the instincts and other tendencies given in the above or in any similar list. In explaining the individual choices which men make, or the desires to which they are subject, there is much scope for the ingenuity of the psychologist. But of the significance for human life of the impulses mentioned there can be no question. What would the life of a man be if he could feel no fear or repulsion? Could there be a development of knowledge in the absence of curiosity? How long would the race endure if the parental instinct were wholly lacking? What would become of a man who never desired food? Could a human society of any sort exist if there were no sympathy or tender feeling, no impulse to seek the company of other men? It is men, such as they are, endowed with the qualities which distinguish man, who associate themselves into communities, and the customs and laws of such reflect the fundamental impulses in which they had their origin. 43. THE STUDY OF MAN'S INSTINCTS IMPORTANT.--That a careful study of human nature is of the utmost importance to the moralist is palpable. He must not prescribe for man a rule of conduct which it is not in man to follow. He must not set before him, as inducements to actions, objects which it is impossible for him to desire and, hence, to choose. To be sure, the main traits of human nature were pretty well recognized many centuries before the modern science of psychology had its birth. Had they not been, man could not have had rational dealings with his fellow- man; could not effectively have persuaded and threatened, rewarded and punished, and, in short, set in motion all the machinery which is at the service of one man when he wants to influence the conduct of another. But moralists ancient and modern have made serious blunders through an imperfect understanding of the impulses natural to man; and the modern psychologist, without claiming to be a wholly original or an infallible guide, may be of no little service in helping us to detect them.