This is a full-length study of a major figure of postwar French intellectual life, who was a champion of socialist humanism. While many Parisian leftists staunchly upheld Marxism in the 1950s and 1960s, Lucien Goldmann insisted that Marxism was by then in severe crisis and had to reinvent itself radically in order to survive. He rejected the traditional Marxist view of the proletariat and contested the structuralist and antihumanist theorizing that infected French left-wing circles in the 1960s. Highly regarded by thinkers as diverse as Jean Piaget and Alasdair MacIntyre, Goldmann is shown here as a socialist who, unlike many others of his time, refused to portray his aspirations for humanity's future as an inexorable unfolding of history's laws. This work summarizes Goldmann's achievements - his genetic structuralist method, his sociology of literature, and his libertarian socialist politics.