Carroll Quigley was a legendary teacher at the Georgetown School of Foreign Service. His course on the history of civilization was extra-ordinary in its scope and on its impact on its students. One of his students was future president Bill Clinton. Clinton named Quigley as an important influence on his aspirations and political philosophy. He mentioned Quigley during his acceptance speech to the 1992 Democratic National Convention. The Evolution of Civilizations is a comprehensive and perspective look at the factors behind the rise and fall of civilizations. Quigley examines the application scientific method to the social sciences. He poses a division of culture into six levels, from the more abstract to the more concrete – intellectual, religious, social, political, economic and military. - and he identifies seven stages of historical change for all civilizations: mixture, gestation, expansion, conflict, universal empire, decay and invasion. He tests these hypothesis by a detailed analysis of five major civilizations: the Mesopotamian, the Canaanite, the Minoan, the classical, and the Western. Quigley defines a civilization as "a producing society with an instrument of expansion." A civilization's decline is not inevitable but occurs when its instrument of expansion is transformed into an institution. Carroll Quigley taught the History of Civilization at Georgetown School of Foreign Service for more than thirty years. A graduate of Harvard University he first taught history there and at Princeton. Professor Quigley was regarded as an expert on the comparative history of civilizations, twentieth century Europe and African Affairs.