=Blundering Instincts.= The older a person is, the more fixed are his habits. Now, an instinct is a race-habit and represents the crystallized reactions of a past that is old. Whatever has been done over and over again, millions of times, naturally becomes fixed, automatic, tending to conserve itself in its old ways, to resist any change and to act as it has always acted. This conserves energy and works well so long as conditions remain the same. But if for any reason there comes a change, things are likely to go wrong. By just so far as things are different, an automatic habit becomes a handicap instead of a help. This having to act under changed conditions is exactly the trouble with the reproductive instinct. Under civilization, conditions have changed but the instinct has not. It is trying to act as it always has acted, but civilized man wills otherwise. The change that has come is not in the physical, external environment, but in man himself and in the social environment which he has created. There is in man an onward urge toward new and better things. Side by side with the desire to live as he always has lived, there is a desire to make new adaptations which are for the advancement of the whole race-life. Besides the natural wish to take his desires as he finds them, there is also the wish to modify them and use them for higher and more socially useful ends. As the race has found through long experience that monogamy is to be preferred to promiscuous mating; that the highest interests of life are fostered by loyalty to the institution of the family; that the careful rearing of several children rather than the mere production of many is in the long run to be desired; and that a single standard of morality is practicable; so society has established for its members a standard which is in direct opposition to the immeasurable urge of the past. To make matters worse, there have at the same time grown up in many communities a standard of living and an economic competition which still further limit the size of the family and the satisfaction of the reproductive impulse.