Robert Blanché

Robert Blanché (1898–1975) was an associate professor of philosophy at the University of Toulouse. He wrote many books addressing the philosophy of mathematics.

About Structures intellectuelles The logical hexagon, co-discovered independently by Blanché and Augustin Sesmat extends the square of opposition to six statements.

Robert Blanché died in 1975. Nine years before, in 1966, he published with Vrin: Structures intellectuelles. Therein, he deals with the logical hexagon. Whereas the logical square or square of Apuleius represents four values: A, E, I, O, the logical hexagon represents six, that is to say, not only A, E, I, O but also two new values: Y and U. It is advisable to read the article: logical hexagon as well what concerns Indian logic.

In La Logique et son histoire d' Aristote à Russell, published with Armand Colin in 1970, Robert Blanché, the author of Structures intellectuelles (Vrin, 1966) mentions that Józef Maria Bocheński speaks of a sort of Indian logical triangle to be compared with the square of Aristotle (or square of Apuleius), in other words with the square of opposition.

Works La Notion de fait psychique, essai sur les rapports du physique et du mental – 1934, ed. PUF. Le Rationalisme de Whewell – 1935, ed. PUF. Whewell : de la construction de la science – 1938, ed. J. Vrin La Science physique et la réalité : réalisme, positivisme, mathématisme - 1948, ed. PUF Les Attitudes idéalistes – 1949, ed. PUF L’Axiomatique – 1955, ed. P.U.F. coll. Quadrige, 112p. Introduction à la logique contemporaine - 1957, ed. Armand Colin, coll Cursus, 205p. Structures intellectuelles, essai sur l’organisation systématique des concepts - 1966, ed. J. Vrin Raison et discours, défense de la logique réflexive – 1967, ed. J. Vrin La science actuelle et le rationalisme - 1967, Ed. PUF. La Méthode expérimentale et la philosophie de la physique – 1969, ed. Armand Collin, 384p La logique et son histoire d’Aristote à Russell, ed. Amand Colin, coll. U, Paris, 1970, 366p. La Logique et son histoire, (avec Jacques Dubucs), ed. Amand Colin, coll. U, Paris, 1996, 396p. (édition revue de 1970) L’Épistémologie - 1972; ed. PUF Le Raisonnement – 1973, ed. PUF L’Induction scientifique et les lois naturelles – 1975, ed. PUF