Bertrand Arthur William Russell, 3rd Earl Russell (18 May 1872 - 2 February 1970) was a British philosopher, logician, mathematician, historian, socialist, pacifist and social critic. Although he spent most of his life in England, he was born in Wales, where he also died. Russell led the British "revolt against idealism" in the early 1900s. He is considered one of the founders of analytic philosophy along with his protégé Wittgenstein and his elder Frege, and is widely held to be one of the 20th century's premier logicians. He co-authored, with A. N. Whitehead, Principia Mathematica, an attempt to ground mathematics on logic. His philosophical essay "On Denoting" has been considered a "paradigm of philosophy." Both works have had a considerable influence on logic, mathematics, set theory, linguistics, and philosophy. He was a prominent anti-war activist, championing free trade between nations and anti-imperialism. Russell was imprisoned for his pacifist activism during World War I, campaigned against Adolf Hitler, for nuclear disarmament, criticised Soviet totalitarianism and the United States of America's involvement in the Vietnam War. In 1950, Russell was awarded the Nobel Prize in Literature, "in recognition of his varied and significant writings in which he champions humanitarian ideals and freedom of thought." (wikipedia.org)