Page:Popular Science Monthly Volume 76.djvu/69

Rh wholly take the place of a lofty and rational idea of marriage, to be brought about by an uplifting of public opinion. It is difficult to bring under the control of the mind a province that has for so long been left almost superstitiously to caprice, but much can be done, in an age of growing social responsibility, to produce a genuine respect and desire for marriage as a necessity to the complete life. More and more we see an appreciation of the immortality achieved by the training up of children to the betterment of the world.

Even if it were possible to attain the ideal working of sexual selection the task of eugenics is not completed.

Fecundal selection, or the principle of descent from those leaving the most numerous offspring, seems to be the most powerful influence in the contemporary evolution of mankind. Throughout the western civilization we find, between 1870 and 1880, the beginning of a marked decline in the birth rate, which, while affecting the backward races least of all, shows no signs of abating at present.

Among the causes of this decrease may be mentioned the more expensive standard of living in civilized countries, the competition of other than domestic activities, greater ambition for the child coupled with greater fluidity of social classes, and, last and most important, a greater knowledge of the physiology of reproduction and the prevention of conception.

Though this general decline in the birth rate gives in itself no special cause for alarm, the serious consideration is that this decline is distributed very unevenly through the social classes. Pearson brings out this point very clearly, the differential character being shown by the fact that in Copenhagen 25 per cent, of one generation is producing from 50 to 60 per cent, of the next. The personnel of this 25 per cent, is not encouraging. The analysis of Pearson, Heron and others for London shows that the decrease in birth rate is greatest among families of the highest income and social position, while Passy gives the birth rate for rich Paris as 1.9, of poor Paris as 2.8. Figures for the United States show that the decline affects American blood far more heavily than that of the immigrants, the Massachusetts birth rate in 1890 being only 2.4 for the native as against 4.3 for the foreign population. The old Puritan families are gradually disappearing—that of John Alden, for instance, will in the next generation be extinct in the male line—while the Finns, Portuguese and French Canadians are spreading over New England. College-bred men and women are apparently failing even to replace themselves, the married members of the Harvard classes above referred to, themselves but a small proportion, having an average of but two surviving children twenty-five years after graduation.