George Orwell made frequent use of the word "totalitarian" and its cognates in multiple essays published in 1940, 1941 and 1942. In his essay "Why I Write", he wrote: "The Spanish war and other events in 1936–37 turned the scale and thereafter I knew where I stood. Every line of serious work that I have written since 1936 has been written, directly or indirectly, against totalitarianism and for democratic socialism, as I understand it". During a 1945 lecture series entitled "The Soviet Impact on the Western World" (published as a book in 1946), the pro-Soviet British historian E. H. Carr claimed: "The trend away from individualism and towards totalitarianism is everywhere unmistakable" and that Marxism–Leninism was by far the most successful type of totalitarianism as proved by Soviet industrial growth and the Red Army's role in defeating Germany. Only the "blind and incurable" could ignore the trend towards totalitarianism, said Carr. In "The Open Society and Its Enemies" (1945) and "The Poverty of Historicism" (1961), Karl Popper articulated an influential critique of totalitarianism: in both works, he contrasted the "open society" of liberal democracy with totalitarianism and argued that the latter is grounded in the belief that history moves toward an immutable future in accordance with knowable laws. In "The Origins of Totalitarianism", Hannah Arendt argued that Nazi and Communist regimes were new forms of government and not merely updated versions of the old tyrannies. According to Arendt, the source of the mass appeal of totalitarian regimes is their ideology, which provides a comforting, single answer to the mysteries of the past, present and future. For Nazism, all history is the history of race struggle and for Marxism-Leninism all history is the history of class struggle. Once that premise is accepted, all actions of the state can be justified by appeal to nature or the law of history, justifying their establishment of authoritarian state apparatus. In addition to Arendt, many scholars from a variety of academic backgrounds and ideological positions have closely examined totalitarianism. Among the most noted commentators on totalitarianism are Raymond Aron, Lawrence Aronsen, Franz Borkenau, Karl Dietrich Bracher, Zbigniew Brzezinski, Robert Conquest, Carl Joachim Friedrich, Eckhard Jesse, Leopold Labedz, Walter Laqueur, Claude Lefort, Juan Linz, Richard Löwenthal, Karl Popper, Richard Pipes, Leonard Schapiro and Adam Ulam.