Relational Semantics for Flat Heyting-Lewis Logic
arXiv:2603.28402 · doi:10.4204/EPTCS.447.25
Abstract
We introduce relational semantics for "flat Heyting-Lewis logic" HLC-flat. This logic arises as the extension of intuitionistic logic with a Lewis-style strict implication modality that, contrary to its "sharp" counterpart HLC-sharp, does not turn meets into joins in its first argument. We prove completeness and the finite model property for HLC-flat and for several extensions with additional axioms.
In Proceedings AiML 2026, arXiv:2606.29444