Russell led the British "revolt against idealism" in the early 20th century. He is considered one of the founders of analytic philosophy along with his predecessor Gottlob Frege, colleague G. E. Moore, and his protégé Ludwig Wittgenstein. He is widely held to be one of the 20th century's premier logicians. Russell was an anti-war activist; he went to prison for his pacifism during World War I. Later, he campaigned against Adolf Hitler, then criticised Stalinist totalitarianism, attacked the involvement of the United States in the Vietnam War. In 1950 Russell was awarded the Nobel Prize in Literature. The Books: The Problems of Philosophy [1912] Mysticism and Logic and Other Essays [1914] Our Knowledge of the External World As a Field for Scientific Method In Philosophy [1914] Political Ideals [1917] Proposed Roads To Freedom [1918] The Practice and Theory of Bolshevism [1920] The Analysis of Mind [1921] Free Thought and Official Propaganda [1922] The Problem of China [1922]