A Dialogue System for Coherent Reasoning with Inconsistent Knowledge Bases

Silvio do Lago Pereira, Luiz Felipe Zarco dos Santos, Lucio Nunes de Lira

Department of Information Technology, FATEC-SP/CEETEPS, São Paulo, Brazil.

DOI: 10.4236/jcc.2015.38002                

Abstract

Traditionally, the AI community assumes that a knowledge base must be consistent. Despite that, there are many applications where, due to the existence of rules with exceptions, inconsistent knowledge must be considered. One way of restoring consistency is to withdraw conflicting rules; however, this will destroy part of the knowledge. Indeed, a better alternative would be to give precedence to exceptions. This paper proposes a dialogue system for coherent reasoning with inconsistent knowledge, which resolves conflicts by using precedence relations of three kinds: explicit precedence relation, which is synthesized from precedence rules; implicit precedence relation, which is synthesized from defeasible rules; mixed precedence relation, which is synthesized by combining explicit and implicit precedence relations.

Keywords

Defeasible Reasoning, Inconsistent Knowledge, Precedence Relation, Dialogue System

Conflicts of Interest

The authors declare no conflicts of interest.

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