We give an exponential lower bound on number of proof-lines in the proof system K of modal logic, i.e., we give an example of K-tautologies 1, 2, . . . s.t. every K-proof of i must...
We present a PSpace algorithm that decides satisfiability of the graded modal logic Gr(KR)—a natural extension of propositional modal logic KR by counting expressions—which pl...
Abstract. Modal logics see a wide variety of applications in artificial intelligence, e.g. in reasoning about knowledge, belief, uncertainty, agency, defaults, and relevance. From ...
We propose so called contraction free sequent calculi for the three prominent modal logics K, T, and S4. Deduction search in these calculi is shown to provide more efficient decisi...
In recent years, a tight connection has emerged between modal logic on the one hand and coalgebras, understood as generic transition systems, on the other hand. Here, we prove tha...