History - the bond between the political scientist and the historian is obvious in the observation that "history is past politics and politics present history." The political scientist frequently adopts a "historical approach" and employs knowledge of the past when he seeks to interpret present and probable developments in political phenomena.
Economics - until late in the 19th century, political science and economics (the study of the production, distribution, and conservation, and consumption of wealth) were coupled under the name of political economy. Today, these fields are jointly concerned with the fact that economic conditions affect the organization, development, and activities of states, which in turn modify or even prescribe economic conditions. The political scientist regularly adopts an"economic approach" when seeking to interpret such matters as "public financial policies"and government regulation of business.
Geography - geopolitics (a science concerned with the study of the influences of physical factors such as population pressures, sources of raw materials, geography, etc. upon domestic and foreign politics) indicates one approach which a political scientist frequently must adopt to help explain such phenomena as the early growth of democracy in Great Britain and the United States and its retarded growth in certain Continental Europe, and the rise of authoritarian governments in developing countries.
Sociology and Anthropology - the political scientist, the sociologist (who specializes in the study of "society as a whole"), and the anthropologist (who studies "mankind" in relation to physical, social and cultural development) are all deeply concerned with the origins and nature of social control and governmental authority, with the abiding influences of race and culture upon society, and with the patterns of collective human behavior.
Psychology - the political scientist as well as the