Ludwig Wittgenstein (1889–1951) came from a wealthy and cultured Jewish family in Vienna. It provided Ludwig with what he later called his “good intellectual nursery-training”. This included Karl Kraus's brilliant polemics against the abuse of language in the late Habsburg Empire, the scientific and philosophical writings of the physicists Heinrich Hertz and Friedrich Boltzmann and the transcendental idealism of Arthur Schopenhauer. From 1906 Wittgenstein studied engineering in Berlin and Manchester. He developed an interest in the foundations of mathematics that led him to the writings of Frege and Russell. In 1911 he went to Cambridge to work with Russell. The Tractatus is the eventual result of this supremely fruitful yet equally fraught intellectual encounter. It was finished in 1918, while Wittgenstein served in the Austrian army, and it remained the only philosophical book he published during his lifetime. He always referred to it as Logisch-Philosophische Abhandlung. Nevertheless, the title G. E. Moore suggested for the English edition, Tractatus Logico-Philosophicus, has carried the day and has become an academic household name. Alas, the work itself has remained obscure. Exegetical controversies rage not just about matters of detail but about the very nature of the book.
It is clear, however, that the Tractatus revolves around the relation between thought and language on the one hand, reality on the other. But its interest in that relation differs fundamentally from the epistemological concerns that dominated Western philosophy after Descartes.