Generalized Epstein Semantics for Parry Systems

Abstract In this paper I introduce a generalized version of Richard Epstein’s set-assignment semantics (Epstein in Propositional Logics. The Semantic Foundations of Logic, vol 1, 2012). As a case study, I consider how this framework can be used to characterize William Parry’s logic of analytic implication and some of its recent variations proposed by Ferguson (Philos Stud 180(7):1849–1879, 2023). In generalized Epstein semantics the parallel use of two algebras, one for extensional and the other for intensional values, allows to account for various forms of content sharing between formulae, which motivates the choice to investigate Parry systems. Hilbert-style axiomatizations and completeness proofs will be presented for all the considered calculi, in particular as main result I provide a set-assignment semantics for Parry’s logic.