Recognizability of All WIP-Minimal Logics

Abstract

We consider extensions of Johansson’s minimal logic J. It was proved in [1] that the weak interpolation property (WIP) is decidable over the minimal logic. Moreover, all logics with WIP are divided into eight pairwise disjoint intervals. The notion of recognizable logic was introduced in [2]. The recognizability over J of five of the eight WIP-minimal logics, i.e. of the lower ends of intervals with WIP, was proved earlier in [2, 3]. We prove the recognizability over J of the remaining three WIP-minimal logics.