Logic of relatives

The logic of relatives, short for the logic of relative terms, is the study of relations in their logical, philosophical, or semiotic aspects, as distinguished from, though closely coordinated with, their more properly formal, mathematical, or objective aspects.The consideration of relative terms has its roots in antiquity, but it entered a radically new phase of development with the work of Charles Sanders Peirce, beginning with his paper "Description of a Notation for the Logic of Relatives, Resulting from an Amplification of the Conceptions of Boole's Calculus of Logic" (1870).
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