Robert Marty

Robert Marty was born on 22 May 1936 in Perpignan, in the Pyrenees Orientales department of southern France, the heartland of Northern Catalonia. He trained as a mathematician and in 1969 defended a doctorat d'etat in mathematics at the University of Paris. His thesis, Sous-groupes fonctoriels et relativisations, dealt with the theory of Abelian groups, and he contributed the chapter Radical, socle et relativisation to a 1968 Springer volume of studies on Abelian groups.

After his work in algebra, Marty turned to the writings of Charles Sanders Peirce, the American logician and philosopher who founded pragmatism and developed a theory of signs. Unlike the two part model of Ferdinand de Saussure, Peirce places the sign within a three way relation of object, sign and interpretant. Working from Peirce's manuscripts, Marty sought to translate this thought into a fuller mathematical formalism, drawing on category theory and the theory of relations.

He demonstrated that the classes of triadic signs are organised in an ordered structure called a lattice, and by the same method obtained the lattices of the 28 classes of hexadic signs and the 66 classes of decadic signs, giving an operational formalisation of Peirce's semiotics. Part of this work formed his second doctorat d'etat, in philosophy, defended in 1987 at Perpignan under Gerard Deledalle, and the book L'algebre des signes: essai de semiotique scientifique d'apres Charles S. Peirce (1990). He also built a thesaurus of 76 definitions of the sign by Peirce, published on peirce.org, the website he created about Peirce.

At the University of Perpignan Via Domitia he founded the Semiocom research group in 1997, and he was a member of the International Center for Transdisciplinary Research (CIRET). His other works included 99 reponses sur la semiotique (1992), later translated into Spanish, and papers on semantic networks, sign flows and epistemology. He held the rank of professor emeritus.

Marty was a well known figure in Perpignan beyond academic life. According to L'Independant, he marched at the head of demonstrations in 1968 and was a sharp observer of politics. He was devoted to Catalan culture and to USAP, the Perpignan rugby club, and in 1998 he published L'USAP, fiers d'etre catalans, a study of the club's phenomenon from the pitch to the stands. Renee Soum, the first woman elected deputy for the Pyrenees Orientales, described him as her lifelong friend.

Robert Marty died on Monday 9 November 2026, aged 90. No cause of death was given. His death was reported by L'Independant on 11 November and by El Punt Avui, which described him as a mathematician of Northern Catalonia. His burial was arranged for Friday 13 November 2026 at 3 p.m. at the Saint Michel cemetery in Canet en Roussillon.

Marty is remembered as one of the scholars who gave Peirce's theory of signs a formal mathematical footing, and his website peirce.org remains a widely used resource on Peirce. His friend Pere Manzanares said he had become a world reference in semiotics, and that in his final weeks he was still researching artificial intelligence tools. Renee Soum said his contribution to knowledge and to passing it on would leave a lasting mark.