On the Notion of Analysis in Peirce's Existential Graphs

JAVIER LEGRIS

SAN PABLO, SP

Congreso; 17th INTERNATIONAL MEETING ON PRAGMATISM; 2017

Centro de Estudos de Pragmatismo, Pontifícia Universidade Católica de São Paulo

C. S. Peirceformulated his conception of deduction in the context of his theory of signs and his pragmaticist philosophy. For him, deduction was a process accomplishedby means of diagrams, and diagrammaticreasoning is the accurate method for representing the course of thinking. From1896 on, Peirce developed his diagrammatic systems of Existential Graphs,considered by him as his chef d'oeuvre that ought to be the logic of the future (according a letter he wrote to William James). Peirce?s approach to logic followed directly from his conception of mathematics: mathematical thought was for him essentially diagrammatic: algebraic equations were as diagrammatic asgeometric figures.Now,diagrams are icons. In a diagram the analytical role of icons turns to beessential. Peirce referred to an icon [or analytic picture] (Peirce CP 1.275).  Anicon provides knowledge through its decomposition in basic elements. There isfurther evidence from unpublished manuscripts that Peirce conceived his systemof the Existential Graphs not only as a diagrammatic proof procedure fordeductive logic, but also (and mainly) as a tool for logical analysis. Clearly, this analysis is not of linguistic butof semiotic nature. Moreover, Peirce regarded his systems of Existential Graphsas the best diagrammatic method fordeductive logic. Hence, they should provide the best (an the most accurate)analysis of logical concepts. This paperaddresses the notion of analysis underlying the Existential Graphs. In linewith this aim, it will be shown that Frederik Stjernfelt?s idea of an operational iconicity provides thesemiotic basis for the notion analysis. Moreover, the claim of Francesco Bellucciand Ahti-Veikko Pietarinen that unique decomposition is the essential feature of Peirce's notion of analysis willbe brought into discussion and will be illustrated by the case of the ?scroll?in the Alpha system of Existential Graphs. Finally, for the sake of a betterunderstanding, Peirce's perspective will be briefly compared with Gottlob Frege' conception of analysis in Begriffsschrift,and some relevant differences between them will be pointed out.