https://hal.inria.fr/inria-00360132Schröder, LutzLutzSchröderDFKI Bremen and Department of Computer Science - Universität BremenPattinson, DirkDirkPattinsonDepartment of Computing [London] - BioMedIA - Biomedical Image Analysis Group [London] - Imperial College LondonStrong Completeness of Coalgebraic Modal LogicsHAL CCSD2009logic in computer sciencesemanticsdeductionmodal logiccoalgebra[INFO.INFO-LO] Computer Science [cs]/Logic in Computer Science [cs.LO]Loria, PublicationsSusanne Albers and Jean-Yves Marion2009-02-10 13:52:162022-01-18 14:26:042009-02-12 17:03:20enConference papershttps://hal.inria.fr/inria-00360132/documentapplication/pdf1Canonical models are of central importance in modal logic, in particular as they witness strong completeness and hence compactness. While the canonical model construction is well understood for Kripke semantics, non-normal modal logics often present subtle difficulties - up to the point that canonical models may fail to exist, as is the case e.g. in most probabilistic logics. Here, we present a generic canonical model construction in the semantic framework of coalgebraic modal logic, which pinpoints coherence conditions between syntax and semantics of modal logics that guarantee strong completeness. We apply this method to reconstruct canonical model theorems that are either known or folklore, and moreover instantiate our method to obtain new strong completeness results. In particular, we prove strong completeness of graded modal logic with finite multiplicities, and of the modal logic of exact probabilities.