There can be little doubt that Louis Althusser was one of the most influential philosophers of the twentieth century, and his influence subsists in many of the concepts currently deployed in disciplines such as cultural studies, social theory and literary criticism. Yet Althusser was also a leading intellectual in the French Communist Party and a foremost participant in the debates in the human sciences that are marked by the names of Claude Lévi-Strauss, Jacques Lacan and Georges Canguilhem. His writings were major interventions in a specific political and theoretical conjuncture and it is this aspect of his work that this new collection of previously untranslated texts seeks to reflect. Consisting of writings from the very height of Althusser’s intellectual powers, during the period 1966-67, this book covers, among other things, the critique of Lévi-Strauss’s structuralism, the theory of discourse and its relationship to psychoanalysis, the place of Ludwig Feuerbach, the tasks of Marxist philosophy, and the famous “humanist controversy.”