Vom Geist der Gesetze
Another example of Montesquieu's anthropological thinking, outlined in "The Spirit of the Laws" and hinted at in "Persian Letters", is his meteorological climate theory, which holds that climate may substantially influence the nature of man and his society. By placing an emphasis on environmental influences as a material condition of life, Montesquieu prefigured modern anthropology's concern with the impact of material conditions, such as available energy sources, organized production systems, and technologies, on the growth of complex socio-cultural systems.