WITTGESTEIN (Ludwig). Tractatus logico-philosophicus followed by Investigations philosophiques. Paris: NRF, Librairie Gallimard, 1961. - In-8, brown banded half-chagrin, smooth spine, untrimmed, cover and spine preserved (modern binding). First edition of the French translation by novelist, philosopher and painter Pierre Klossowski of the "Tractatus logico-philiosophicus", a major work by the Austrian-born English philosopher Ludwig Wittgenstein (1889-1951). It is followed by a collection of thoughts entitled "Philosophical Investigations". The edition was prefaced by Bertrand Russel and published by Gallimard in the "Bibliothèque des idées" collection. There was no large paper edition. A precious copy, from the press office, given by Klossowki to SIMONE DE BEAUVOIR and enriched with this autograph letter signed on the false title: "Pour // Madame Simone de Beauvoir // en respectueux hommage // Pierre Klossowki." It includes several reading marks and a pencil note on page 113, in an unknown hand. A good copy in modern binding, despite the slightly faded spine. Cover slightly browned. Provenance: Simone de Beauvoir, with consignment from the translator.