A nonmonotonic logic for reasoning about speech acts and belief revision
A prerequisite to a theory of the way agents understand speech acts is a theory of how their beliefs and intentions are revised as a consequence of events. This process of attitude revision is an interesting domain for the application of nonmonotonic reasoning because speech acts have a conventional aspect that is readily represented by defaults, but that interacts with an agent's beliefs and intentions in many complex ways that may override the defaults. Perrault has developed a theory of speech acts, based on Rieter's default logic, that captures the conventional aspect; it does not, however, adequately account for certain easily observed facts about attitude revision resulting from speech acts. A natural theory of attitude revision seems to require a method of stating preferences among competing defaults. We present here a speech act theory, formalized in hierarchic autoepistemic logic (a refinement of Moore's autoepistemic logic), in which revision of both the speaker's and hearer's attitudes can be adequately described. As a collateral benefit, efficient automatic reasoning methods for the formalism exist. The theory has been implemented and is now being employed by an utterance-planning system.
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- Douglas E. Appelt. Planning English Sentences. Cambridge University Press, Cambridge, England, 1985.Google Scholar
- Philip R. Cohen. On Knowing What to Say: Planning Speech Acts. PhD thesis, University of Toronto, 1978.Google Scholar
- Philip R. Cohen and H. Levesque. Speech acts and rationality. In Proceedings of the 23rd Annual Meeting, pages 49–59, Association for Computational Linguistics, 1985.Google Scholar
- Philip R. Cohen and H. Levesque. Rational Interaction as the Basis for Communication. Technical Report, Center for the Study of Language and Information, 1987.Google Scholar
- Philip R. Cohen and C. Raymond Perrault. Elements of a plan-based theory of speech acts. Cognitive Science, 3:117–212, 1979.Google Scholar
- D. W. Etherington and R. Reiter. On inheritance hierarchies with exceptions. In Proceedings of AAAI, 1983.Google Scholar
- Kurt Konolige. Hierarchic autoepistemic theories for nonmonotonic reasoning: preliminary report Appearing in this volume.Google Scholar
- Vladmir Lifschitz. Computing circumscription. In Proceedings of AAAI, pages 121–127, 1985.Google Scholar
- Drew McDermott. Nonmonotonic logic II: nonmonotonic modal theories. Journal of the Association for Computing Machinery, 29(1):33–57, 1982.Google Scholar
- Robert C. Moore. Semantical considerations on nonmonotonic logic. Artificial Intelligence, 25(1), 1985.Google Scholar
- Raymond Reiter. A logic for default reasoning. Artificial Intelligence, 13, 1980.Google Scholar
- Yoav Shoham. Reasoning about Change: Time and Causation from the Standpoint of Artificial Intelligence. MIT Press, Cambridge, Massachusetss, 1987.Google Scholar