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KI - Künstliche Intelligenz

, Volume 33, Issue 1, pp 9–33 | Cite as

A Brief Survey on Forgetting from a Knowledge Representation and Reasoning Perspective

  • Thomas Eiter
  • Gabriele Kern-IsbernerEmail author
Technical Contribution
  • 115 Downloads

Abstract

Forgetting is an ambivalent concept of (human) intelligence. By definition, it is negatively related to knowledge in that knowledge is lost, be it deliberately or not, and therefore, forgetting has not received as much attention in the field of knowledge representation and reasoning (KRR) as other processes with a more positive orientation, like query answering, inference, or update. However, from a cognitive view, forgetting also has an ordering function in the human mind, suppressing information that is deemed irrelevant and improving cognitive capabilities to focus and deal only with relevant aspects of the problem under consideration. In this regard, forgetting is a crucial part of reasoning. This paper collects and surveys approaches to forgetting in the field of knowledge representation and reasoning, highlighting their roles in diverse tasks of knowledge processing, and elaborating on common techniques. We recall forgetting operations for propositional and predicate logic, as well as for answer set programming (as an important representative of nonmonotonic logics) and modal logics. We discuss forgetting in the context of (ir)relevance and (in)dependence, and explicit the role of forgetting for specific tasks of knowledge representation, showing its positive impact on solving KRR problems.

Keywords

Forgetting Knowledge representation and reasoning Logic Answer set programming Nonmononotonic reasoning Modal logics Interpolation Relevance Independence 

Notes

Acknowledgements

The authors are grateful to the reviewers for their constructive comments to improve this article. This work was partly supported by DFG Priority Programme 1921 Intentional Forgetting. The first author is grateful to DFG for supporting his attendance of the internal workshop of the Programme in Limburg, Germany, May 3–4, 2018.

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Copyright information

© Springer-Verlag GmbH Germany, part of Springer Nature 2018

Authors and Affiliations

  1. 1.Institute of Logic and ComputationTU WienViennaAustria
  2. 2.Department of Computer ScienceTU DortmundDortmundGermany

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