Martial Gueroult (ɡeʁu; 15 December 1891 – 13 August 1976) was a French philosopher. His primary areas of research were in 17th- and 18th-century philosophy as well as the history of philosophy. Gueroult was born on 15 December 1891 in the city of Le Havre in northwestern France. A veteran of both the First and Second World Wars, he was awarded the Légion d’Honneur [Legion of Honour] and twice with the Croix de Guerre [Cross of War]. It was during his time as a prisoner of war in Germany that Gueroult began drafting his first philosophical work on Johann Gottlieb Fichte, later to become L’Évolution et la structure de la doctrine de la science chez Fichte [The Evolution and Structure of Fichte’s Doctrine of Science]. Gueroult’s first academic appointment was to the University of Strasbourg. In the 1930s, Gueroult spent some time at the University of São Paulo in Brazil where he worked along with other French intellectuals such as Roger Bastide, Claude Lévi-Strauss, Pierre Monbeig and Ferdinand Braudel to develop the newly founded university’s social science programs. He would return to France to accept a position at the Sorbonne but in 1951, was named successor to Étienne Gilson at the Collège de France. Gueroult re-titled his position as "Histoire et technologie des systèmes philosophiques" ["History and Technology of Philosophical Systems"] and it is here he would remain until his retirement in 1962. Gueroult's work was characterized by a close attention to the History of Philosophy—which he considered as noble as philosophy itself—as well as a strong demand for systematicity. He also refused philosophical recourse to transcendence. A polemical debate opposed him to Ferdinand Alquié concerning Descartes, as Gueroult was studying him "according to the order of reasons" (synchronically), while Alquié was more interested in his historical evolution, studying him diachronically. Gueroult was interested in the "conditions of possibility of a history of philosophy" in general.