OLENDER@SRI-WARBUCKS.ARPA (Margaret Olender) (07/09/86)
ON THE RELATION BETWEEN DEFAULT THEORIES AND AUTOEPISTEMIC LOGIC Kurt Konolige (KONOLIGE@SRI-AI) Artificial Intelligence Center SRI International and CSLI, Stanford University 11:00 AM, MONDAY, July 14 SRI International, Building E, Room EK228 Default theories are a formal means of reasoning about defaults: what normally is the case, in the absence of contradicting information. Autoepistemic theories, on the other hand, are meant to describe the consequences of reasoning about ignorance: what must be true if a certain fact is not known. Although the motivation and formal character of these systems are different, a closer analysis shows that they bear a common trait, which is the indexical nature of certain elements in the theory. In this paper we treat both autoepistemic and default theories as special cases of a more general indexical theory. The benefits of this analysis are that it gives a clear (and clearly intuitive) semantics to default theories, and combines the expressive power of default and autoepistemic logics in a single framework. VISITORS: Please arrive 5 minutes early so that you can be escorted up from the E-building receptionist's desk. Thanks!