The relative importance of heredity or environmental influence remains an enduring, hotly debated issue, while the legacy of scientific racism and sexism still tarnishes the twenty-first century. This unique study analyzes how theories of inherited difference - including race and gender - affected French social scientists in the late-nineteenth and early twentieth centuries.

The prevailing assumption has been that French ethnographers highlighted the cultural and social environment while anthropologists emphasized the scientific study of head and body shapes. Martin Staum shows that the temptation to gravitate towards one pole of the nature-nurture continuum often resulted in reluctant concessions to the other side. Psychologists Théodule Ribot and Alfred Binet, for example, were forced to recognize the importance of social factors. Non-Durkheimian sociologists were divided on the issue of race and gender as progressive and tolerant attitudes on race did not necessarily correlate with flexible attitudes on gender. Recognizing this allows Staum to raise questions about the theory of the equivalence of all marginalized groups.

Anthropological institutions re-organized before the First World War sometimes showed decreasing confidence in racial theory but failed to abandon it completely. Staum's chilling epilogue discusses how the persistent legacy of such theories was used by extremist anthropologists outside the mainstream to deploy racial ideology as a basis of persecution in the Vichy era.