Bertrand Russell (1872-1970) was a wide-ranging thinker best known for his work in the foundations of mathematics and analytic philosophy. He was also a political activist, a moral theorist, an educational innovator, and a gifted popularizer of concepts widely believed to be too deep for the general public (like the theory of relativity). He was an English Lord (an Earl), who inherited his title from his grandfather John Russell, a former prime minister.
Orphaned at the age of 3, Russell was raised by his grandparents (the former prime minister and his wife) who went to court to gain custody of Bertrand and his brother from the younger, more progressive guardians named their father's will. The elderly Russells provided a household that was politically liberal, religiously conservative, strict, and rather old-fashioned. Bertrand was educated by tutors and had little contact with other children his age. Much of his career can be interpreted as a revolt against his upbringing. Though he held onto (and radicalized) many of his grandparents' liberal political views, he rejected their religion, and throughout his life was unable to think of religion as anything other than old-fashioned, traditional, judgmental, and superstitious. His attraction to abstract studies like philosophy and mathematics was a marked contrast to his grandfather's worldly practicality. His liberal educational theories were a rejection of the form his own education, and his ethical writings (especially his views about sex) were a rejection of the content. When he skewers Victorian nostalgia in Chapter 2 of Conquest, he speaks from childhood experience that he is not the least bit nostalgic for.
Russell's politics were always controversial. He viewed World War I as a kind of mass insanity (and was personally annoyed that it interrupted his collaboration with Ludwig Wittgenstein). He was imprisoned for pacifism in 1918, a great scandal for a Lord. He espoused socialism for much of his life, and was one of many liberal intellectuals to give credibility to the Soviet Union when he visited in the 1920s. After World War II he was a leader in the movements to encourage nuclear disarmament and to protest the Vietnam War.
With his second wife, he founded the experimental progressive Beacon Hill School in 1931. (He was married four times and divorced three times.) His appointment to the faculty of City College in New York was revoked in 1940 after public protests concerning his personal life and writings about sexual morality.
He wrote many popular essays, some of which have been collected in books like Why I Am Not a Christian and Mysticism and Logic. He received the Nobel Prize for Literature in 1950.