Ways Things Can't Be



Notre Dame Journal of Formal Logic

Ways Things Can't Be

Greg Restall

Source: Notre Dame J. Formal Logic Volume 38, Number 4 (1997), 583-596.

Abstract

Paraconsistent logics are often semantically motivated by considering "impossible worlds." Lewis, in "Logic for equivocators," has shown how we can understand paraconsistent logics by attributing equivocation of meanings to inconsistent believers. In this paper I show that we can understand paraconsistent logics without attributing such equivocation. Impossible worlds are simply sets of possible worlds, and inconsistent believers (inconsistently) believe that things are like each of the worlds in the set. I show that this account gives a sound and complete semantics for Priest's paraconsistent logic LP, which uses materials any modal logician has at hand.

Primary Subjects: 03B53
Secondary Subjects: 03A05, 03B45
Links and Identifiers

Permanent link to this document: http://projecteuclid.org/euclid.ndjfl/1039540771
Mathematical Reviews number (MathSciNet): MR1648854
Digital Object Identifier: doi:10.1305/ndjfl/1039540771
Zentralblatt MATH identifier: 0916.03015

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