Modal logic, an extension of classical logic, investigates the modes of truth such as necessity and possibility. Its development has been closely intertwined with advances in proof theory, a field ...

The unification problem in a normal modal logic is to determine, given a formula φ, whether there exists a substitution σ such that σ(φ) is in that logic. In that case, σ is a unifier of φ. We shall ...

This is a preview. Log in through your library . Abstract Jaśkowski's discussive logic D₂ was formulated with the help of the modal logic S5 as follows (see [7, 8]): A ∊ D₂ iff ┌ A ┐ ∊ S5, where (-) ...

Tradition states that above the entrance to Plato’s Academy were inscribed the words, “Let no one ignorant of geometry enter here.” A student in the modal logic interim course studies how subjunctives ...

15:00 - 15:15 Katsuhiko Sano and Sakiko Yamasaki: Subformula property and Craig interpolation theorem of sequent calculi for tense logics Valentin Shehtman and Dmitry Shkatov: Some prospects for ...

Papers on related subjects will also be considered. (1) Full papers for publication in the proceedings and presentation at the conference. (2) Short presentations intended for presentation at the ...