Murray Bookchin (January 14, 1921 – July 30, 2006) was an American social theorist, author, orator, historian, and political philosopher. Influenced by G. W. F. Hegel, Karl Marx, and Peter Kropotkin, he was a pioneer in the environmental movement. Bookchin formulated and developed the theory of social ecology and urban planning within anarchist, libertarian socialist, and ecological thought. He was the author of two dozen books covering topics in politics, philosophy, history, urban affairs, and social ecology. Among the most important were ''Our Synthetic Environment'' (1962), ''Post-Scarcity Anarchism'' (1971), ''The Ecology of Freedom'' (1982), and ''Urbanization Without Cities'' (1987). In the late 1990s, he became disenchanted with what he saw as an increasingly apolitical "lifestylism" of the contemporary anarchist movement, stopped referring to himself as an anarchist, and founded his own libertarian socialist ideology called "communalism", which seeks to reconcile and expand Marxist, syndicalist, and anarchist thought.