Translations between interior preorder structures and coherent neighbourhood systems for intuitionist modal logic

Abstract

On this article we provide a relation between two inherently different semantic structures for intuitionistic modal logic. We start by recalling the Heyting Algebras, then defining the language and the axioms for the iS4h intuitionistic calculus. We then proceed to analyse two structures discussed on [4] and their relation. Finally, we discuss about a structure defined on [3, Chapter 6], establishing properties in order for it to be sound with iS4h, and finally conclude that it is semantically equivalent to the other two structures defined by [4].