The philosopher who fell silent for seven years after one book

Wittgenstein carried his manuscript in his pack through the trenches of World War I while completing the 'Tractatus Logico-Philosophicus.' Believing he had solved every problem of philosophy, he left the field entirely and became a village schoolteacher.

In the book, he concluded that we must remain silent about what cannot be clearly stated in language. Since our understanding of the world is bound by the structure of language, expanding the limits of language means expanding the limits of thought itself.