In summary the book elaborates Grant's interpretation of contemporary anthropology and history, which he sees as revolving chiefly around the idea of race rather than environment. He specifically promotes the idea of the Nordic race as a key social group responsible for human development; thus the subtitle of the book is The Racial Basis of European History. Grant also supports eugenics, advocating the sterilization of "undesirables", a treatment possibly to be extended to "types which may be called weaklings" and "perhaps ultimately to worthless race types":