Contradiction: When Avoidance Equals Removal - Part II
نویسندگان
چکیده
This paper is the continuation of 1] in this volume. There we present a sceptical semantics which avoids contradiction for extended logic programs plus integrity contraints in the form of denials, based on the notion of optative hypotheses {an abductive approach. In this part we deene a program revision method for removing contradiction from contradictory programs under WFSX, based on the notion of revisable hypotheses {a belief revision approach{ and show the equivalence between the contradiction avoidance semantics and the WFSX of revised programs obtained by contradiction removal. The motivation, as well as some preliminary deenitions can be found in 1]. Proofs of all theorems are omitted for brevity, but exist in an extended version of this work.
منابع مشابه
Contradiction: When Avoidance Equals Removal - Part I
Recently several authors have stressed and illustrated the importance of including a second kind of negation (explicit negation) in logic programs besides \negation as failure", and its use in deductive databases, knowledge representation, and nonmonotonic reasoning. By introducing explicit negation into logic programs contradiction may appear. In this work we present two approaches for dealing...
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