Through a detailed reading of Karl Mannheim's early explorations in the sociology of knowledge, this book argues for Mannheim's relevance for contemporary social and political theory. As a philosophical project of self-reflection, the early sociology of knowledge is distinctive for its blend of Marxist social theory and phenomenological investigation, making it a valuable resource for current philosophical attempts to relate thought to its social conditions. Furthermore, the struggle documented in the early days of this project – against social critique's tendency to obscure its own perspective – provides the best standard by which to assess its own limitations.