 The four-field approach understood not merely as bringing together different kinds of anthropologists into one department, but as reconceiving anthropology through the integration of different objects of anthropological research into one overarching object, was one of Boas's fundamental contributions to the discipline, and came to characterize American anthropology against that of
England, France, or Germany.This approach defines as its object the human species as a totality.This focus did not lead Boas to seek to reduce all forms of humanity and human activity to some lowest common denominator; rather, he understood the essence of the human species to be the tremendous variation in human form and activity (an approach that parallels Charles Darwin's approach to species in general).