On possibilistic modal logics defined over MTL-chains

Abstract

In this paper we revisit a 1994 paper by Hájek et al. where a modal logic over a finitely-valued Lukasiewicz logic is defined to capture possibilistic reasoning. In this paper we go further in two aspects: first, we generalize the approach in the sense of considering modal logics over an arbitrary finite MTL-chain, and second, we consider a different possibilistic semantics for the necessity and possibility modal operators. The main result is a completeness proof that exploits similar techniques to the ones involved in Hájek et al.’s previous work.