C. S. Peirce?s Existential Graphs beyond the Distinction of Logic as

JAVIER LEGRIS

TALLIN

Workshop; History and Philosophy of Logic Notations; 2015

Tallinn University of Technology - CHAIR OF PHILOSOPHY

In the last period of his thinking and due to philosophical reasons, C. S. Peircedeveloped a diagrammatic system for logic, his Existential Graphs. Deductionwas for him the construction and manipulation of a diagram with iconicfunctions. Jaakko Hintikka tried to determinate and describe Peirce?s locus inthe framework of the traditions of ?Logic as Calculus? and ?Logic as Language?in the history of symbolic logic, placing it in the first tradition. Hintikka?sclaim was mainly guided by the model-theoretic aspects of Peirce?s work. Inthis paper, it will be argued that Hintikka?s distinction presupposes a linguisticconception of logic, which is not Peirce?s own ultimate conception. When Peirceclaimed that the Existential Graphs were ?not intended to serve as a universallanguage for mathematicians or other reasoners like that of Peano? ( Peirce, CP4.424), he was ruling out a linguistic conception of logic. Thus, it can besuggested that Peirce was, in some sense, beyond this distinction. Moreover, itwill be argued that Peirce?s conception could be better understood as part ofthe tradition of symbolic knowledge, stemming from Leibniz, that is strongrelated to the origins of semiotics.