Gilles Deleuze was a philosopher. Felix Guattari is a psychoanalyst. The life and joint work of these most important figures of French intellectual life in the second half of the 20th century is a vivid example of the political and intellectual flowering during the period of May 1968. Deleuze (1925–1995) taught philosophy at the experimental University of Vincennes and, drawing on a deep understanding of the history of philosophy, undertook the unique work of creating concepts. Félix Guattari (1930–1992) was a professional psychoanalyst and one of Lacan's early students. A participant in numerous left-wing movements, he practiced at the La Borde psychiatric clinic and created a self-governing research group in 1966, the Center for Institutional Research and Education. Their introduction to each other in 1969 would mark the beginning of a great friendship and unprecedented intellectual adventures. Beginning with Anti-Oedipus and ending with A Thousand Plateaus and What is Philosophy?, the two of them will write works unparalleled in their conceptual inventiveness and diversity of references, aimed at combating psychoanalysis and capitalism. In this double biography of François Doss, drawing on unpublished archival materials and extensive interviews with numerous witnesses, reveals the logic of the work, connecting theory and experiment, concept creation, critical thought and social practice. Doss explores the secrets of a unique joint creativity that forms a separate page of our intellectual history, which has not lost its relevance to this day. The publishing layout is preserved in PDF A4 format.