Cornelius Castoriadis audaciously defined philosophy as the act of ‘taking responsibility for the totality of the thinkable [prise en charge de la totalité du pensable]’. His life and work attest to the intensity with which he dedicated himself to this project. If he sometimes lamented the lack of major philosophic voices in an era when academic interpretations of the past had come to dominate ‘professional thinking’, he almost single-handedly made up for it himself. A quintessential iconoclast who admitted suffering from an éros du savoir, he broke through the ideological torpor of French academic and political circles, and he established one of the most original and comprehensive bodies of work in twentieth-century European philosophy.

Born in 1922 to a Greek family that had immigrated to Constantinople, Castoriadis grew up in pre-war Athens and moved to Paris in 1945 to study philosophy. In Paris, he co-founded, with Claude Lefort, the revolutionary group and journal Socialisme ou barbarie (published from 1949 to 1965). The journal distanced itself from Trotskyism and broke in more or less fundamental ways with Marxism. It provided a radical critique of bureaucracy, arguing in favour of a revolutionary socialism founded on workers’ management, and many have argued that it had a direct impact on the events of 1968. Castoriadis wrote under pseudonyms until the 1970s, once he had been naturalised as a French citizen. From 1948 until 1970, he worked as an economist at the Organisation for Economic Co-operation and Development. In 1973, he began working as a trained psychoanalyst, and he was named Directeur d’études at the École des Hautes Études en Sciences Sociales in 1981. He passed away in Paris in 1997.

The quintessential dissident, Castoriadis cut across the rigid structures of academic life and stalwartly refused the simple dividing lines between theoretical endeavours and practical engagements. His work impressively spans across the fields of philosophy, political theory, sociology, history, economics, psychoanalysis and the philosophy of science.