Pitirim A. Sorokin, a Russian-born American sociologist, wrote extensively on such subjects as the sociology of knowledge, the sociology of art, political sociology, social stratification, and methodology. A scholar of enormous learning, he attempted to analyze the processes of social organization, disorganization, and reorganization---all within a panoramic view of history that stressed periodic fluctuation as the heart of social change. Sorokin moved to the United States in 1922 after he was banned from the Soviet Union because of his opposition to the Bolshevik regime; during the revolution of 1917, he had been a member of the Constituent Assembly, the private secretary of Prime Minister Kerensky, and the editor of a newspaper. In the United States, he taught at the University of Minnesota and then at Harvard University. His Social and Cultural Dynamics (1937--41), contains his sociological interpretation of history. His Fads and Foibles of Modern Sociology and Related Sciences (1956) is a comprehensive methodological critique of the quantification and formalization of sociocultural phenomena that he believed characterized sociology in the United States.