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Why defeasible deontic logic needs a multi preference semantics

  • Yao-Hua Tan
  • Leendert W. N. der Torre
Conference paper
Part of the Lecture Notes in Computer Science book series (LNCS, volume 946)

Abstract

There is a fundamental difference between a conditional obligation being violated by a fact, and a conditional obligation being overridden by another conditional obligation. In this paper we analyze this difference in the multi preference semantics of our defeasible deontic logic DefDiode. The semantics contains one preference relation for ideality, which can be used to formalize deontic paradoxes like the Chisholm and Forrester paradoxes, and another preference relation for normality, which can be used to formalize exceptions. The interference of the two preference orderings generates new questions about preferential semantics.

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References

  1. 1.
    C. Boutilier. Toward a logic for qualitative decision theory. In Proceedings of KR'94, 1994.Google Scholar
  2. 2.
    B.F. Chellas. Modal Logic: An Introduction. Cambridge University Press, 1980.Google Scholar
  3. 3.
    R.M. Chisholm. Contrary-to-duty imperatives and deontic logic. Analysis, 24:33–36, 1963.Google Scholar
  4. 4.
    J.W. Forrester. Gentle murder, or the adverbial Samaritan. Journal of Philosophy, 81:193–197, 1984.Google Scholar
  5. 5.
    J.F. Horty. Deontic logic founded in nonmonotonic logic. Annals of Mathematics and Artificial Intelligence, 9:69–91, 1993.Google Scholar
  6. 6.
    A.J.I. Jones and M. Sergot. Deontic logic in the representation of law: Towards a methodology. Artificial Intelligence and Law, 1:45–64, 1992.Google Scholar
  7. 7.
    A.J.I. Jones and M. Sergot. Proceedings of the Second Workshop on Deontic Logic in Computer Science (Deon'94). Oslo, 1994.Google Scholar
  8. 8.
    D. Makinson. Five faces of minimality. Studia Logica, 52:339–379, 1993.Google Scholar
  9. 9.
    L.T. McCarty. Defeasible deontic reasoning. In Fourth International Workshop on Nonmonotonic Reasoning, Plymouth, 1992.Google Scholar
  10. 10.
    J.-J. Meyer and R. Wieringa. Deontic Logic in Computer Science: Proceedings of the First Workshop on Deontic Logic in Computer Science (Deon '91). John Wiley & Sons, 1993.Google Scholar
  11. 11.
    H. Prakken. Logical Tools for Modelling Legal Argument, Ph-D thesis. Amsterdam, 1993.Google Scholar
  12. 12.
    H. Prakken and M.J. Sergot. Contrary-to-duty imperatives, defeasibility and violability. In Proceedings of the Second Workshop on Deontic Logic in Computer Science (Deon'94), Oslo, 1994.Google Scholar
  13. 13.
    Y. Shoham. Reasoning About Change. MIT Press, 1988.Google Scholar
  14. 14.
    Y.-H. Tan and L.W.N. van der Torre. Representing deontic reasoning in a diagnostic framework. In Proceedings of the Workshop on Legal Applications of Logic Programming of the Eleventh International Conference on Logic Programming (ICLP'94), 1994.Google Scholar
  15. 15.
    L.W.N. van der Torre. Violated obligations in a defeasible deontic logic. In Proceedings of the Eleventh European Conference on Artificial Intelligence (ECAI'94), pages 371–375. John Wiley & Sons, 1994.Google Scholar
  16. 16.
    L.W.N. van der Torre and Y.-H. Tan. Cancelling and overshadowing: two types of defeasibility in defeasible deontic logic. Technical Report WP 95.02.01, Euridis, 1995. To appear in: Proceedings of the IJCAI-95.Google Scholar

Copyright information

© Springer-Verlag Berlin Heidelberg 1995

Authors and Affiliations

  • Yao-Hua Tan
    • 1
  • Leendert W. N. der Torre
    • 1
    • 2
  1. 1.EuridisErasmus University RotterdamDR RotterdamThe Netherlands
  2. 2.Tinbergen Institute and Department of Computer ScienceErasmus University RotterdamDR RotterdamThe Netherlands

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