Quite a lot is known about Wittgenstein’s life, although not everything is completely understood. Some stories seem to be in the realm of legends. Wittgenstein was born in 1889 in Vienna, Austria, to a famous and wealthy family of Jewish ancestry. His paternal grandparents were Jews who converted to Protestantism, and his mother was Catholic, although her father was of Jewish descent. Ludwig was the youngest of eight children, who were all exposed to high culture (composer Johannes Brahms was a friend of the family).

Although Ludwig was baptized as a Catholic, when he “confessed his sins” to friends later in life, among his admitted transgressions was the fact that he allowed others to assume he was not Jewish. Ludwig had four brothers, three of whom committed suicide. When his father died in 1913, Ludwig inherited a vast fortune, which he gave away. In 1938, after Germany annexed Austria, he was able to protect his sisters from being sent to concentration camps by giving the German government millions of dollars in gold.

Wittgenstein’s education included studying mechanical engineering in Berlin; in 1908 he moved to England to study aeronautics, which included experimenting with kites. This led to mathematics and then to philosophy, insofar as it was a current pursuit to seek the foundations of mathematics in logic. A visit with the mathematician Gottlob Frege (1848–1925) led Wittgenstein to meet Bertrand Russell (1872–1970) at Cambridge University, where he studied logic with both G.E. Moore (1873–1958) and Russell. But his studies were interrupted by World War I, during which he volunteered for the Austrian army and distinguished himself for bravery.

Russell assisted Wittgenstein in publishing Tractatus Logico-Philosophicus (1922). Wittgenstein then taught elementary school in a rural area of Austria and also designed and built a modernist house in Vienna for his sister Gretl.

Returning to Cambridge in 1929, he taught philosophy, becoming a professor at Trinity College 10 years later. He was a hospital porter during World War II and resigned his professorship in 1947, moving to Ireland to write. Just before dying, he said, “Tell them I’ve had a wonderful life.” Ray Monk’s biography Wittgenstein: The Duty of Genius (1991) is considered definitive as both an intellectual and personal account of Wittgenstein’s life.