Ludwig Wittgenstein

Ludwig Josef Johann Wittgenstein ( VIT-gən-s(h)tyne; Austrian German: [ˈluːdvɪk ˈjoːsɛf ˈjoːhan ˈvɪtɡn̩ʃtaɪn]; 26 April 1889 – 29 April 1951) was an Austro-British philosopher who worked in logic, philosophy of mathematics, philosophy of mind, and philosophy of language.

Wittgenstein was born in Vienna into one of Europe's richest families. From 1911 to 1913, he studied at the University of Cambridge under Bertrand Russell and interacted closely with John Maynard Keynes and G. E. Moore, among others. During this time, he inherited a fortune, part of which he donated to various poets and artists and the rest of which he gave to his siblings. He also began what would become his first important philosophical work. However, at the start of World War I, he left academia to enlist in the Austro-Hungarian Army. After a series of personal adversities—including the death of his older brother by suicide (the third of his older brothers to die by suicide during his lifetime), the death of his close friend and perhaps lover David Pinsent, and his imprisonment in an Italian prisoner of war camp—he became depressed. He worked as a schoolteacher around Vienna. Despite these setbacks, his philosophical work was published in the Tractatus Logico-Philosophicus in 1921, followed by an English translation in 1922 with help from Frank P. Ramsey, to considerable discussion and acclaim.

At the encouragement of Russell, Keynes, and Ramsey, Wittgenstein returned to Cambridge, where he taught from 1930 to 1947, giving lectures on philosophy, often permeated by his original research. During World War II, he left academia again to work at the Guy's Hospital in London and at the Royal Victoria Infirmary in Newcastle upon Tyne. Wittgenstein would not publish another philosophical work during his lifetime, but following his death in 1951, his voluminous manuscripts were edited and published posthumously. The first and best-known of this posthumous series is the 1953 book Philosophical Investigations.