Modal Nonmonotonic Logics: Ranges, Characterization, Computation

In the paper, we investigate the way in which nonmonotonic modal logics depend on their underlying monotonic modal logics. Most notably, we study when different monotonic modal logics define the same nonmonotonic system. In particular, we show that for an important class of the so called stratified theories all nonmonotonic logics considered in the paper, with the exception of S5, coincide. It turns out that in some cases, nonstandard (that is, non-normal) logics have interesting nonmonotonic counterparts. Two such systems are investigated in the paper in detail. For the case of finite theories, all nonmonotonic logics considered are shown to be decidable and an appropriate algorithm is presented.

• Type: Conference
• Year: 1991
• Where: KR
• Authors: V. Wiktor Marek, Grigori F. Shvarts, Miroslaw Truszczynski
• Keywords: Automated Reasoning, KR 1991, Modal Logics, Monotonic Modal Logics, Nonmonotonic Modal Logics