Local Tabularity is Decidable for Bi-Intermediate Logics of Trees and of Co-Trees

Miguel Martins, Tommaso Moraschini

A bi-Heyting algebra validates the Gödel-Dummett axiom $(p\to q)\vee (q\to p)$ iff the poset of its prime filters is a disjoint union of co-trees (i.e., order duals of trees). Bi-H…