Repairing Description Logic Ontologies by Weakening Axioms

TL;DR

This paper introduces a gentle repair method for Description Logic ontologies that weakens axioms instead of deleting them, aiming to preserve more intended consequences while removing unwanted ones.

Contribution

It proposes and analyzes a novel axiom weakening approach for repairing EL ontologies, offering a less destructive alternative to axiom deletion.

Findings

The weakening method effectively removes unwanted consequences.

It preserves more intended consequences compared to deletion.

The approach is theoretically analyzed and practically applicable.

Abstract

The classical approach for repairing a Description Logic ontology O in the sense of removing an unwanted consequence $\alpha$ is to delete a minimal number of axioms from O such that the resulting ontology O' does not have the consequence $\alpha$. However, the complete deletion of axioms may be too rough, in the sense that it may also remove consequences that are actually wanted. To alleviate this problem, we propose a more gentle way of repair in which axioms are not necessarily deleted, but only weakened. On the one hand, we investigate general properties of this gentle repair method. On the other hand, we propose and analyze concrete approaches for weakening axioms expressed in the Description Logic EL.