Wittgenstein Wrote His Only Book in the Trenches and Then Quit Philosophy

Ludwig Wittgenstein joined the Austro-Hungarian army as a volunteer two days after the outbreak of the First World War. He fought on the Russian and Italian fronts, won the Silver Medal of Valor twice, and carried his philosophical notebooks in his rucksack. He finished what would become the Tractatus Logico-Philosophicus on a summer leave in 1918, weeks before he was captured at Trento. He spent the rest of the war in an Italian POW camp at Cassino, where he sent a copy of the manuscript to Bertrand Russell.

The book is structurally strange. It consists of 525 hierarchically numbered declarative statements — 1, 1.1, 1.11, 1.12 — and contains essentially no arguments. When Russell, drafting the introduction for the 1922 English edition, suggested adding a few, Wittgenstein wrote back to refuse on aesthetic grounds. The Latin title was G. E. Moore's idea, in homage to Spinoza's Tractatus Theologico-Politicus. Russell's introduction got the book a publisher; Wittgenstein later said Russell had badly misunderstood the work.

The most surprising fact about the Tractatus is what its author did next. He believed the book had solved every philosophical problem worth solving, that the result was that most of philosophy was nonsense, and that the only honest response to this conclusion was to stop. He gave away the substantial fortune he had inherited from his father, trained as a primary-school teacher, and spent the years 1920–1926 teaching nine-year-olds in three remote Austrian villages. He returned to Cambridge in 1929 only after meetings with Vienna Circle philosophers convinced him there were things in the Tractatus he now thought were wrong. The later Wittgenstein, the one who matters most, was a refutation of his own first book.