In [Sas01], it was given a cut-free sequent system for the smallest interpretability logic IL. He first gave a cut-free system for IK4, a sublogic of IL, whose -free fragment is th...
Order-sorted logic is a useful tool for knowledge representation and reasoning because it enables representation of sorted terms and formulas along with partially ordered sorts (c...
One can add the machinery of relation symbols and terms to a propositional modal logic without adding quantifiers. Ordinarily this is no extension beyond the propositional. But if...
Polyadic coalgebraic modal logic is studied in the setting of locally presentable categories. It is shown that under certain assumptions, accessible functors admit expressive logi...
A propositional system of modal logic is second-order if it contains quantifiers p and p, which, in the standard interpretation, are construed as ranging over sets of possible worl...