Imre Lakatos (1922-1974) was one of the protagonists in shaping the "new philosophy of science". His main theme of locating rationality within the scientific process appears even more compelling today, after many historical case studies have revealed the cultural and societal elements within scientific practices. There has been an increasing interest in Lakatos' philosophy of mathematics, which emphasizes heuristics and mathematical practice over logical justification. But suitable modifications of his approach are called for in order to make it applicable to modern axiomatized theories. Historical research in England and Hungary has unearthed facts about Lakatos' personal life, his wartime activities and his involvement in the political developments of post-war Europe. From a communist activist committed to Gyorgyi Lukacs' thinking, Lakatos developed into a staunch anti-Marxist who found his intellectual background in Popper's critical rationalism.