Signature Entrenchment and Conceptual Changes in Automated Theory Repair

TL;DR

This paper introduces a method to evaluate the importance of logical components in automated theory repair, enabling more intuitive and plausible conceptual changes in artificial knowledge systems.

Contribution

It presents a formal approach to measure signature entrenchment in logical theories, guiding automated repairs to produce more meaningful conceptual modifications.

Findings

Signature entrenchment quantifies the inferential contribution of logical elements.

The method constrains repairs to maintain valuable concepts.

Provides a basis for comparing automated and human judgments of conceptual change.

Abstract

Human beliefs change, but so do the concepts that underpin them. The recent Abduction, Belief Revision and Conceptual Change (ABC) repair system combines several methods from automated theory repair to expand, contract, or reform logical structures representing conceptual knowledge in artificial agents. In this paper we focus on conceptual change: repair not only of the membership of logical concepts, such as what animals can fly, but also concepts themselves, such that birds may be divided into flightless and flying birds, by changing the signature of the logical theory used to represent them. We offer a method for automatically evaluating entrenchment in the signature of a Datalog theory, in order to constrain automated theory repair to succinct and intuitive outcomes. Formally, signature entrenchment measures the inferential contributions of every logical language element used to express conceptual knowledge, i.e., predicates and the arguments, ranking possible repairs to retain valuable logical concepts and reject redundant or implausible alternatives. This quantitative measurement of signature entrenchment offers a guide to the plausibility of conceptual changes, which we aim to contrast with human judgements of concept entrenchment in future work.