Dialogue modelling in M-KRYPTON-a hybrid language for multiple believers

The authors describe an attempt to combine insights from knowledge representation and epistemic logic. Hybrid knowledge representation systems embody a powerful representational paradigm, accounting for multiple, essentially different kinds of belief (or, popularly, knowledge) in an integrated way. On the other hand, the possible-worlds semantics typical of epistemic logic is easily tailored to model various interesting notions, such as the existence of multiple believers and introspective belief. By recasting the KRYPTON hybrid KR system in terms of possible-worlds semantics the authors have obtained a semantic account that, besides being `functionality´ equivalent to the original one, is easily extensible to deal with operators (such as those for `propositional attitudes´) that have traditionally been the subject of epistemic and related logics. In particular, the authors have concentrated on adding to KRYPTON the possibility of representing beliefs about the beliefs of multiple agents