5 papers
Fischer-Servi logic does not have interpolation
Rodrigo Nicolau Almeida, Nick Bezhanishvili, Simon Lemal
We prove that the Fischer-Servi logic does not have the (Craig) interpolation property. This is obtained by showing that the corresponding class of modal Heyting alge…
Superamalgamation for modal lattices via non-distributive dualities
Rodrigo Nicolau Almeida, Nick Bezhanishvili, Simon Lemal
We show that the variety of modal lattices has the superamalgamation property. As a consequence, we obtain that the weak positive modal logic has the Craig interpolation property.…
Structural Completeness in bi-IPC
Rodrigo Nicolau Almeida, Nick Bezhanishvili
In this note we show that no extension of bi-intuitionistic logic, except for classical logic, is structurally complete; indeed, none of them are passively structurally complete. A…
A Coalgebraic Semantics for Intuitionistic Modal Logic
Rodrigo Nicolau Almeida, Nick Bezhanishvili
We give a new coalgebraic semantics for intuitionistic modal logic with . In particular, we provide a colagebraic representation of intuitionistic descriptive modal frames an…
-Rule Systems and Inductive Classes of Gödel Algebras
Rodrigo Nicolau Almeida
In this paper we present a general theory of -rules for systems of intuitionistic and modal logic. We introduce the notions of -rule system and of an Inductive Class,…