{"type":"ScholarlyArticle","title":"Possibilistic Logic, Preferential Models, Non-monotonicity and Related Issues","authors":[{"name":"Didier Dubois","slug":"didier-dubois","given":"Didier","family":"Dubois","affiliation":""},{"name":"Henri Prade","slug":"henri-prade","given":"Henri","family":"Prade","affiliation":""}],"abstract":"The links between Shoham's preference logic and possibilistic logic, a numerical logic of uncertainty based on Zadeh's possibility measures, are investigated. Starting from a fuzzy set of preferential interpretations of a propositional theory, we prove that the notion of preferential entailment is closely related to a previously introduced notion of conditional possibility. Conditional possibility is then shown to possess all properties (originally stated by Gabbay) of a well-behaved non-mo~~t?n~c consequence relation. We obtain the possibihstic counterpart of Adams' E-sem.antics of condi~i?n~l probabilities which is the basis of the probabilistic model of non-monotonic logic proposed by Geffner and Pearl. Lastly we prove that our notion of possibilistic entailment is the one at work ~n possibilistic logic, a logic that ha~dle~ uncertam propositional formulas, where uncertainty IS model~ed by degrees of necessity, and where partial inconsistency is allowed. Considering the formerly established close links between Gru-denfors'epistemic entrenchment and necessity·measures, what this paper proposes is a new way of relating belie~ revisi~n. a!'d non-monotonic inference, namely via possibility theory.","doi":null,"url":"https://ijcai.org/proceedings/1991/63","pdf":"https://ijcai.org/proceedings/1991/0063.pdf","markdown":"https://ijcai.org/proceedings/1991/63.md","bibtex":"https://ijcai.org/proceedings/1991/bibtex/63","volume":{"slug":"1991","title":"Proceedings of the Twelfth International Joint Conference on Artificial Intelligence","short_title":"IJCAI 1991","url":"https://ijcai.org/proceedings/1991/","year":1991,"location":"Sydney, New South Wales, Australia","dates":"24-30 August 1991","editors":"John Mylopoulos and Ray Reiter","isbn":"","publisher":"International Joint Conferences on Artificial Intelligence","doi_prefix":""},"section":"Knowledge Representation","track":"Knowledge Representation","number":63,"pages":{"first":419,"last":424},"keywords":[],"videos":[],"references":[],"license_note":"Copyright International Joint Conferences on Artificial Intelligence."}