Ludwig Wittgenstein

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 the 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.

Wittgenstein's philosophy is often divided into an early period, exemplified by the Tractatus, and a later period, articulated primarily in the Philosophical Investigations. The "early Wittgenstein" was concerned with the logical relationship between propositions and the world, and he believed that by providing an account of the logic underlying this relationship, he had solved all philosophical problems.

The "later Wittgenstein" rejected many of the assumptions of the Tractatus, arguing that the meaning of words is best understood as their use within a given language game. Wittgenstein was well regarded among academics during his lifetime, and was decorated for his courage during World War I. However, he encountered controversy during his time teaching for his use of violent corporal punishment on girls and boys (see the Haidbauer incident).

His work (both early and later) has been described as controversial and sparked a number of different reactions. Late