Bulletin of the Section of Logic Volume 37:3/4 (2008), pp. 185–196 Krystyna Mruczek-Nasieniewska Marek Nasieniewski PARACONSITENT LOGICS OBTAINED BY J.-Y. B ´ EZIAU’S METHOD BY MEANS OF SOME NON-NORMAL MODAL LOGICS Abstract The paper presents a formulation of some propositional logics. In [2] J.-Y. B´ eziau formulated a logic called Z. J.-Y. B´ eziau’s idea was generalized independently in [7] and [8]. The present paper (based on results from [8]) is a contribution to a further generalization for those frames in which non-normal worlds are allowed. Introduction The main point of the logic Z was to understand negation as “it is possible that not” [2]. While defining this logic, B´ eziau used modal logic S5. In the present paper we are using B´ eziau’s negation in the case of modal log- ics expressible by Kripke semantics where non-normal worlds are allowed. Considered logics turn out to be paraconsistent. 1. Class R Definition 1. Let For be the set of all propositional formulae in the language with connectives {∼, , , , ↔} and the set of propositional variables Var.