Badiou is the son of the mathematician Raymond Badiou (1905–1996), who was a working member of the Resistance in France during World War II. Alain Badiou was a student at the Lycée Louis-Le-Grand and then the École Normale Supérieure (1955–1960). In 1960, he wrote his "" (roughly equivalent to an MA thesis) on Spinoza for Georges Canguilhem (the topic was "Demonstrative Structures in the First Two Books of Spinoza's Ethics", "Structures démonstratives dans les deux premiers livres de l'Éthique de Spinoza"). He taught at the lycée in Reims from 1963 where he became a close friend of fellow playwright (and philosopher) François Regnault, and published a couple of novels before moving first to the faculty of letters of the University of Reims (the "collège littéraire universitaire") and then to the University of Paris VIII (Vincennes-Saint Denis) in 1969. Badiou was politically active very early on, and was one of the founding members of the Unified Socialist Party (PSU). The PSU was particularly active in the struggle for the decolonization of Algeria. He wrote his first novel, "Almagestes", in 1964. In 1967 he joined a study group organized by Louis Althusser, became increasingly influenced by Jacques Lacan and became a member of the editorial board of "Cahiers pour l'Analyse". By then he "already had a solid grounding in mathematics and logic (along with Lacanian theory)", and his own two contributions to the pages of "Cahiers" "anticipate many of the distinctive concerns of his later philosophy".