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 the Popular 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.
PAUL POPENOE.
Washington, June, 1918.