Alcohol and the other narcotics produce much the same results. On the question as to what extent drunkenness is due to flabby moral fiber, there has been dispute. Archdall Reid declares[1] that alcohol taken to excess is an "agent of elimination at once selective and very stringent. It weeds out great numbers of individuals of a particular type—those most susceptible to its charm." This authority thinks moral resistance to alcoholic temptation of small consequence; men, he says, "indulge in it in proportion to their desires." On this point there is naturally much dissent, but there is no need that we enter the controversy. Certain men are swamped by alcohol and other-men left. In so far as the moral factor determines the incidence of this selective force, we have elimination of the anti-social.
Finally we may note one more agency which works for the increase of social tractability. The various factors we have mentioned so far have been mainly phases of lethal selection; now we turn for a moment to sexual and reproductive selection. In every generation there are persons who are debarred or abstain from wedlock. Among the men who enter matrimony a certain proportion desert their wives or are divorced. There is, further, a wide-spread practise, rapidly growing in our day, of placing voluntary restraints on child-bearing.
Now persons who do not mate with the opposite sex, or mated, refuse to have children, are sometimes those whose social sympathies are feeble. The domestic virtues are the social virtues par excellence. We could never breed a race of misogamists, nor are we in any danger of populating the earth with a race of women militant against men. Along with many other results we perhaps have here some elimination of the anti-social. But we do not care to stress this point. The motives which lead to voluntary childlessness are numerous and mixed, and the final influence on the racial inheritance seems most disastrous, since it substantially results in a continuous sterilization of the better stocks. All things considered, this is the gravest difficulty that the eugenists have to face.
III
The foregoing hasty summary of the more important factors which have conferred survival value on altruism and tractability has, it is hoped, given some appearance of solidity to the contention that there has been a steady elimination of the anti-social throughout historic times. It is not argued that we have here an explanation of all the moral differences between the civilizations of antiquity and of the present. The increments of knowledge, the growth of cohesive social and political institutions and the betterment of economic conditions, have all played a part in knitting the moral fabric of the world of
- ↑ "The Principles of Heredity," p. 195.
