In this book Dr Dubos, an editor of the Journal of Experimental Medicine, examines the environmental forces affecting the history of social groups from the precursors of homo sapiens to man today. Considering characteristics unique to humanity, he states that 'Man can function well only when his external environment is in tune with the needs he has inherited from his evolutionary, experiential, and social past, and with his aspirations for the future.'

As man acquires much of his personality through responses to environment, Dr Dubos discusses the complex interrelations that govern life today, and the effects of environment on the health of primitive and modern man. In non-technical language he surveys the control of life, biomedical philosophies and the possibilities of a science of man. Precisely because they are concerned with various aspects of humanity, Dr Dubos believes that 'the biomedical sciences in their highest form are potentially the richest expression of science.'