Unification in lax logic

Document Type : Original Article


1 Universit`a degli Studi di Milano, Department of Mathematics, via Cesare Saldini 50, 20133 Milano

2 DIPMAT, University of Salerno, Italy


In this paper, we focus on the intuitionistic propositional logic extended with a local operator [22] (also called nucleus [21]); such logic is commonly named lax logic after [9]. We prove that unification is finitary in this logic and supply algorithms for computing a basis of unifiers and for recognizing admissibility of inference rules, following analogous known results for intuitionistic logic.