Besnard, Philippe and Moinard, Yves Non-classical Default Logics , IPMU'98 , EDK, Éditions Médicales et Scientifiques, Paris , La Sorbonne, Paris , 1116--1121 , jul , 1998 Abstract Default logic extends classical logic through specific reasoning patterns yielding tentative conclusions. Many authors have found purported counter-examples to default logic and they have proposed non-classical default logics (that is, a non-classical logic is used as underlying system). This paper is meant to show that there can be a stronger motivation for non-classical logics, and that is the existence of properties enjoyed by such variants but not by default logic itself. This web site is maintained by René Quiniou using the Weave system from the Caravel project: http://www-caravel.inria.fr. Last modification: 10-07-2011 09:54:25