Bertrand Arthur William Russell (1872 - 1970), the third Earl Russell, was a philosopher and influential logician, an important political liberal, activist and a popularizer of philosophy. Millions looked up to Russell as a sort of prophet of the creative and rational life; at the same time, his stance on many topics was extremely controversial. He was born in 1872, at the height of Britain's economic and political ascendancy, and died in 1970 when Britain's empire had all but vanished and her power had been drained in two victorious but debilitating world wars. At his death, however, his voice still carried moral authority, for he was one of the world's most influential critics of nuclear weapons and the American war in Vietnam. In 1950, Russell was made Nobel Laureate in Literature "in recognition of his varied and significant writings in which he champions humanitarian ideals and freedom of thought".

Russell's philosophical and logical work
In mathematical logic, Russell established Russell's paradox, which exposed an inconsistency in naive set theory and led directly to the creation of modern axiomatic set theory. He defended logicism (the view that mathematics is in some important sense reducible to logic) by creating, withAlfred North Whitehead, the Principia Mathematica, a clean axiomatic system on which all of mathematics can be built, but which was never fully completed. Russell is generally recognized as one of the founders of analytic philosophy. His most influential contributions include his theories of definite descriptions and logical atomism. Wittgenstein was his student, but he disagreed with Wittgenstein's later linguistic approach to philosophy.

Russell's activism
Russell was an outspoken pacifist. He opposed England's participation in World War I and as a result was first fined, then lost his professorship at Trinity College of Cambridge University and later imprisoned for six months. In the years leading to World War II, he supported the policy of appeasement, but later acknowledged thatHitler had to be defeated.
Indeed, on November 20, 1948, in a public speech at Westminster School, Russell advocated a preemptive nuclear strike against the Soviet Union. Addressing a gathering arranged by a peace-loving foundation, Russell shocked most of his listeners by advising that a preemptive nuclear strike on the Soviets would be a humanitarian gesture, as it would foreclose the chance of going to full nuclear war with the Soviets in the future, a confrontation sure to be far more devastating to the world. Starting in the 1950s, Russell became a vocal opponent of nuclear weapons, released a manifesto together with AlbertEinstein and organized several conferences. In 1961, he was imprisoned for a week in connection with his nuclear disarmament protests. He opposed the Vietnam War and along withJean-Paul Sartre organized a tribunal intended to expose American war crimes. In matters of religion, Russell classified himself as a philosophical agnostic and a practical atheist. He wrote that his attitude towards the Christian God was the same as his attitude towards the Greek gods: strongly convinced that they don't exist, but not able to rigorously prove it. His position is explained in the essaysAm I An Atheist Or An Agnostic? andWhy I am not a Christian. While a socialist at heart, he was extremely critical of the totalitarianism exhibited by Stalin's regime.

Taken from:
http://en.wikipedia.org/wiki/Bertrand_Russell
http://www.malaspina.com/site/person_1013.asp

Also see:

http://www.mcmaster.ca/russdocs/russell1.htm
http://plato.stanford.edu/entries/Russell
http://www.nobel.se/literature/laureates/1950/press.html

http://www-groups.dcs.st-and.ac.uk/~history/Mathematicians/Russell.html

http://www.royalinstitutephilosophy.org/articles/cam_russell.htm

http://plato.stanford.edu/entries/russell/
http://www.users.drew.edu/~jlenz/brtexts.html