Variations of constrained default logic
Recently a variant of Reiter's default logic, called constrained default logic, has been developed in order to overcome certain short-comings of the original approach. In this paper, we introduce a very simple but powerful extension of constrained default logic, called preconstrained default logic. We demonstrate that adding certain preconstraints to default theories results in very expressive systems: Apart from representing heuristic control information, pre-constraints provide simple mechanisms for dealing with default lemmas and for incorporating priorities. Finally, we describe how pre-constrained default logic is related to other well-known approaches.
KeywordsTheorist Extension Default Theory Default Logic Default Reasoning Powerful Extension
Unable to display preview. Download preview PDF.
- 1.G. Brewka. Nonmonotonic Reasoning: Logical Foundations of Commonsense. Cambridge University, 1991.Google Scholar
- 2.J. Delgrande, K. Jackson, T. Schaub. Alternative approaches to default logic. Submitted, June 1992.Google Scholar
- 3.J. Dix. On cumulativity in default logic and its relation to Poole's approach. In B. Neumann, ed., Proc. of ECAI'92, 289–293. Wiley, 1992.Google Scholar
- 4.D. Makinson. General theory of cumulative inference. In M. Reinfrank et al., eds., Proc. 2nd NMR Workshop, 1–18. Springer, 1989.Google Scholar
- 5.D. Poole. A logical framework for default reasoning. Artificial Intelligence, 36:27–47, 1988.Google Scholar
- 6.D. Poole. What the lottery paradox tells us about default reasoning. In R. Brachman et al., eds., Proc. of KR'89, 333–340. Morgan Kaufmann, 1989.Google Scholar
- 7.R. Reiter. A logic for default reasoning. Artificial Intelligence, 13(1–2):81–132, 1980.Google Scholar
- 8.T. Schaub. On commitment and cumulativity in default logics. In R. Kruse, ed., Proc. of ECSQAU'91, 304–309. Springer, 1991.Google Scholar
- 9.T. Schaub. On constrained default theories. In B. Neumann, ed., Proc. of ECAI'92, 304–308. Wiley, 1992.Google Scholar