 Environmental determinism, environmental determinism also known as climatic determinism or geographical determinism is the study of how the physical environment predisposes societies and states towards particular development trajectories. 19th century approaches helped that climate and terrain largely determined human activity and psychology, and it was associated with institutionalized racism and eugenics. Many scholars underscored that this approach supported colonialism and Eurocentrism, and devalued human agency in non-Western societies. Gerald Diamond, Geoffrey Herbst, Ian Morris, and other social scientists sparked the revival of the theory during the late 20th and early 21st centuries. This neo-environmental determinism school of thought examines how geographic and ecological forces influence state building, economic development, and institutions.