On Coherence Approach to Logic Program Revision
Li-Yan Yuan, Jia-Huai You · The MIT Press eBooks · 1995
We present a new approach to revising extended programs, based on the coherence theory initially advocated by Gardenfors for belief revision. We define the skeptical and credulous coherence semantics and show that both semantics can be characterized in terms of the fixpoint semantics of a revised program using a simple program revision technique. Semantical properties and advantages of the proposed revision semantics are also analyzed. 1 Introduction The extension of logic programs with classical negation significantly increases the expressive power of logic programs, but also presents new challenges [7]. Among other things, the contradictory problem brought up by classical negation has to be addressed. Unlike normal programs, an extended program with classical negation may not be consistent. For example, \\Pi = f:a /; a /; b /g is considered contradictory since both a and :a can be derived from it. Many attempts have been made to resolve the contradictory problem. However, almost all...