|"Eugenics is the self-direction of human evolution": Logo from the Second International Eugenics Congress, 1921 (Photo credit: Wikipedia)|
The science of eugenics consists of a foundation of biology and a superstructure of sociology. Galton, its founder, emphasized both parts in due proportion. Until recently, however, most sociologists have been either indifferent or hostile to eugenics, and the science has been left for the most part in the hands of biologists, who have naturally worked most on the foundations and neglected the superstructure. Although we are not disposed to minimize the importance of the biological part, we think it desirable that the means of applying the biological principles should be more carefully studied. The reader of this book will, consequently, find only a summary explanation of the mechanism of inheritance. Emphasis has rather been laid on the practical means by which society may encourage the reproduction of superior persons and discourage that of inferiors.
We assume that in general, a eugenically superior or desirable person has, to a greater degree than the average, the germinal basis for the following characteristics: to live past maturity, to reproduce adequately, to live happily and to make contributions to the productivity, happiness, and progress of society. It is desirable to discriminate as much as possible between the possession of the germinal basis and the observed achievement, since the latter consists of the former plus or minus environmental influence. But where the amount of modification is too obscure to be detected, it is advantageous to take the demonstrated achievement as a tentative measure of the germinal basis. The problem of eugenics is to make such legal, social and economic adjustments that (1) a larger proportion of superior persons will have children than at present, (2) that the average number of offspring of each superior person will be greater than at present, (3) that the most inferior persons will have no children, and finally that [Pg vi](4) other inferior persons will have fewer children than now. The science of eugenics is still young and much of its program must be tentative and subject to the test of actual experiment. It is more important that the student acquire the habit of looking at society from a biological as well as a sociological point of view, than that he put his faith in the efficacy of any particular mode of procedure.
The essential points of our eugenics program were laid down by Professor Johnson in an article entitled "Human Evolution and its Control" in thePopular Science Monthly for January, 1910. Considerable parts of the material in the present book have appeared in the Journal of Heredity. Helpful suggestions and criticism have been received from several friends, in particular Sewall Wright and O. E. Baker of the United States Department of Agriculture.