One of America's most influential social critics, Thorstein Veblen authored works deeply rooted in evolutionary biology and American philosophical naturalism - both of which help explain his institutional economics and radical sociology. Now Rick Tilman ranges widely over the man's writings to show how evolutionary naturalism underlies his social theory and criticism, shapes his satire, and binds his work together. Tilman's study focuses on the intersections of social theory and social psychology, political economy and political theory, and modern philosophy and intellectual history in Veblen's thinking. It links evolutionary naturalism for the first time to Veblen's aesthetics, secular humanism, sociology of control, sociobiology, and sociology of knowledge, and it makes groundbreaking observations regarding the relationship of Veblen's own life to his thinking; his place as a cultural lag theorist; and his analysis of sports, gambling, and religion. Drawing on textual exegesis of Veblen's work. unpublished correspondence, and selected archives, Tilman argues that only evolutionary naturalism could provide the philosophical foundations of Veblen's thought. He also emphasizes Veblen's role in the enhancement and embellishment of the social sciences and cultural studies, as well as his insights into the processes of change in the sociopolitical order.