Explanation-based closure of databases with hypotheses
Koji Matsuda, Ikuo Tahara · Systems and Computers in Japan · 1997
This paper proposes a generalization of the closed-world assumption, called the explanation-based generalized closed-world assumption (EGCWA), as a logical framework to discuss commonsense reasoning for a database including hypotheses. The EGCWA is based on the notion that a statement with no explanation from hypotheses should be assumed false. The semantics for the EGCWA is considered, and it is shown that the model of the EGCWA is such that the set of true hypotheses is maximal. On the basis of this result, the relation between the EGCWA and other types of formalizations of commonsense reasoning, that is, circumscription and default reasoning, is discussed. Finally, an algorithm for determining whether or not a ground sentence holds in the EGCWA is presented. © 1997 Scripta Technica, Inc. Syst Comp Jpn. 28 (1): 56–65, 1997