Conservative belief revision

James P. Delgrande, Abhaya C. Nayak, Maurice Pagnucco

Research output: Chapter in Book/Report/Conference proceedingConference proceeding contributionpeer-review


A standard assumption underlying traditional accounts of belief change is the principle of minimal change, that an agent’s belief state should be modified minimally to incorporate new information. In this paper we introduce a novel account of belief change in which the agent’s belief state is modified minimally to incorporate exactly the new information. Thus a revision by p V q will result in a new belief state in which p v q is believed, but a stronger proposition (such as p & q) is not, regardless of the initial form of the belief state. This form of belief change is termed conservative belief change and corresponds to a Gricean interpretation of the input formula. We investigate belief revision in this framework, and provide a representation result between a set of postulates characterising this form of belief change and a construction in terms of systems of spheres. This approach is extended to that of belief revision with respect to a specified context. Last, we show how this approach resolves a longstanding problem in belief revision.
Original languageEnglish
Title of host publicationProceedings
Subtitle of host publicationNineteenth National Conference on Artificial Intelligence (AAAI-04) : Sixteenth Innovative Applications of Artificial Intelligence Conference (IAAI-04)
EditorsDeborah L. McGuinness, George Ferguson
Place of PublicationCalifornia, USA
PublisherAssociation for the Advancement of Artificial Intelligence
Number of pages6
ISBN (Print)9780262511834
Publication statusPublished - 2004
EventNational Conference on Artificial Intelligence (19th : 2004) - San Jose, Calif.
Duration: 25 Jul 200429 Jul 2004


ConferenceNational Conference on Artificial Intelligence (19th : 2004)
CitySan Jose, Calif.

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