Abstract
One of the most important and difficult problems in logic programming is the problem of finding a suitable declarative or intended semantics for logic programs. The importance of this problem stems from the declarative character of logic programming, whereas its difficulty can be largely attributed to the non-monotonic character of the negation operator used in logic programs. The problem can therefore be viewed as the problem of finding a suitable formalization of the type of non-monotonic reasoning used in logic programming.
In this paper we introduce a semantics of logic programs based on the class PERF(P) of all, not necessarily Herbrand, perfect models of a program P and we show that the proposed semantics is not only natural but it also combines many of the desirable features of previous approaches, at the same time eliminating some of their drawbacks. For a positive program P, the class PERF(P) of perfect models coincides with the class MIN(P) of all minimal models of P.
The perfect model semantics is shown to be equivalent to the semantics of McCarthy's circumscription and is also equivalent to the remaining three major formalizations of non-monotonic reasoning in artificial intelligence-Reiter's closed world assumption, Moore's autoepistemic logic and Reiter's default theorythus establishing a closer link between the areas of logic programming and non-monotonic reasoning.
We also define a generalization of SLD-resolution, called SLS-resolution and we prove that SLS-resolution is sound and complete with respect to the perfect model semantics.
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K. Apt, personal communication.
K. Apt, H. Blair, and A. Walker, ‘Towards a Theory of Declarative Knowledge’, in: Foundations of Deductive Databases and Logic Programming, (ed. J. Minker), Morgan Kaufmann 1987, 89–148.
K. Apt and M.Van Emden, ‘Contributions to the Theory of Logic Programming’, JACM 29, 841–862 (1982).
N. Bidoit and C. Froidevaux, ‘Minimalism Subsumes Default Logic and Circumscription in Stratified Logic Programming’, preprint.
N. Bidoit and R. Hull, ‘Positivism vs. Minimalism in Deductive Databases’, Proceedings ACM SIGACT-SIGMOD Symposium on Principles of Database Systems, Cambridge, Mass., March 1986, 123–132.
G. Bossu and P. Siegel, ‘Saturation, Nonmonotonic Reasoning and the Closed World Assumption’, Artificial Intelligence 25, 13–63 (1985).
A. Chandra and D. Harel, ‘Horn Clause Queries and Generalizations’, Journal of Logic Programming 1, 1–15 (1985).
D. Chan, ‘Constructive negation Based on the Completed Database’, Proceedings Logic Programming Conference, Seattle, Wash. 1988.
K. L. Clark, ‘Negation as Failure’, in: Logic and Data Bases (H. Gallaire and J. Minker, Eds.), Plenum Press, New York 1978, 293–322.
D. Etherington, ‘Reasoning with Incomplete Information. Investigations of Non-Monotonic Reasoning’, PhD Thesis, Dept. of Computer Science, University of British Columbia, 1986.
D. Etherington, R. Mercer, and R. Reiter, ‘On the Adequacy of Predicate Circumscription for Closed-World Reasoning’, Computational Intelligence, 1, 11–15 (1985).
M. Fitting, ‘A Kripke-Kleene Semantics for Logic Programs’, Journal of Logic Programming 2, 295–312 (1985).
D. Gabbay, ‘Modal Provability Foundations for Negation as Failure. I’, preprint.
H. Gallaire, J. Minker, and J. Nicolas, ‘Logic and Databases: A Deductive Approach’, Computing Surveys 16, 153–185 (1984).
M. Gelfond, ‘On Stratified Autoepistemic Theories’, Proceedings AAAI-87, Seattle, Washington, August 1987.
M. Gelfond, H. Przymusinska, and T. Przymusinski, ‘The Extended Closed World Assumption and its Relationship to Parallel Circumscription’, Proceedings ACM SIGACT-SIGMOD Symposium on Principles of Database Systems, Cambridge, Mass., March 1986, pp. 133–139.
M. Gelfond, H. Przymusinska, and T. Przymusinska, ‘On the Relationship between Circumscription and Negation as Failure’, Artificial Intelligence, in press.
M. Gelfond, H. Przymusinska, and T. Przymusinska, ‘Minimal Model Semantics vs. Negation as Failure: A Comparison of Semantics’, Proceedings of the ACM SIGART International Symposium on Methodologies for Intelligent Systems, Torino, Italy, 1988, pp. 335–343.
J. Jaffar, J-L. Lassez, and J. Lloyd, ‘Completeness of the Negation as Failure Rule’, IJCAI-83, Karlsruhe, 1983, pp. 500–506.
J. Jaffar, J-L. Lassez, and M. Maher, ‘Some Issues and Trends in the Semantics of Logic Programming’, Proceedings ICLP3, London.
D. Kemp and R. Topor, ‘Completeness of a Top-Down Query Evaluation Procedure for Stratified Databases’, Proceedings Logic Programming Conference, Seattle, Wash. 1988, pp. 178–194.
K. Kunen, ‘Negation in Logic Programming’, J. Logic Programming 3 (1986).
K. Kunen, ‘Answer Sets and Negation as Failure’, Proceedings ICLP4, Melbourne, 1987.
J-L. Lassez and M. Maher, ‘Optimal Fixpoints of Logic Programs’, Theoretical Computer Science 39, 15–25 (1985).
V. Lifschitz, ‘On the Declarative Semantics of Logic Programs with Negation’, in: Foundations of Deductive Databases and Logic Programming (ed. J. Minker), Morgan Kaufmann 1987, pp. 177–192.
V. Lifschitz, ‘Computing Circumscription’, Proceedings IJCAI-85, Los Angeles 1985, pp. 121–127.
J. W. Lloyd, Foundations of Logic Programming, Springer-Verlag, 1984.
J. W. Lloyd, Foundations of Logic Programming, Springer-Verlag, 1987 (Second Edition).
J. W. Lloyd and R. W. Topor, ‘Making Prolog More Expressive’, J. Logic Programming 1, 225–240 (1984).
J. W. Lloyd and R. W. Topor, ‘A Basis for Deductive Database Systems II’, J. Logic Programming 3, 55–67 (1986).
J. McCarthy, ‘Circumscription — a Form of Non-Monotonic Reasoning’, Artificial Intelligence 13, 27–39 (1980).
J. McCarthy, ‘Applications of Circumscription to Formalizing Common Sense Knowledge’, AAAI Workshop on Non-Monotonic Reasoning 1984, pp. 295–323.
J. Minker, ‘Perspectives in Deductive Databases’, University of Maryland Tech. Report 1987.
J. Minker, ‘On Indefinite Data Bases and the Closed World Assumption’, Proc. 6th Conference on Automated Deduction, Springer Verlag, 1982, pp. 292–308.
S. A. Naqvi, ‘A Logic for Negation in Database Systems’, preprint 1986.
H. Przymusinska, ‘On the Relationship between Autoepistemic Logic and Circumscription for Stratified Databases’, Proceedings of the International Symposium on Methodologies of Intelligent Systems, Charlotte, N. C., October 1987, pp. 445–452.
T. Przymusinski, ‘On the Declarative Semantics of Stratified Deductive Databases and Logic Programs’, in: Foundations of Deductive Databases and Logic Programming (ed. J. Minker), Morgan Kaufmann 1987, pp. 193–216.
T. Przymusinski, ‘On Constructive Negation in Logic Programming’, to appear.
T. Przymusinski, ‘Non-Monotonic Reasoning vs. Logic Programming: A New Perspective’, in: Formal Foundations of Artificial Intelligence (eds. D. Partridge and Y. Wilks), Cambridge University Press, to appear (extended abstract in: ‘On the Relationship Between Non-monotonic Reasoning and Logic Programming’, Proceedings of AAAI'88, St. Paul, Minn., 1988, pp. 444–448).
T. Przymusinski, ‘Three-valued Non-monotonic Formalisms and Logic Programming’, Proceedings of the International Conference of Knowledge Representation and Reasoning (KR '89), Toronto, Canada, May 1989, in press.
T. Przymusinski, ‘Every Logic Program Has a Natural Stratification and an Iterated Fixed Point Model’, Proceedings of the Conference on Principles of Database Systems (PODS '89), Philadelphia, Pa, March 1989, in press.
R. Reiter, ‘Towards a Logical Reconstruction of Relational Database Theory’, in: On Conceptual Modeling (M. Brodie et al., eds.), Springer Verlag 1984, pp. 191–233.
R. Reiter, ‘On Closed-World Data Bases’, in: Logic and Data Bases (H. Gallaire and J. Minker, eds.), Plenum Press, New York 1978, pp. 55–76.
R. Seki and H. Itoh, ‘A Query Evaluation Method for Stratified Programs under the Extended CWA’, Proceedings Logic Programming Conference, Seattle, Wash. 1988, 195–211.
J. Shepherdson, ‘Negation as Failure: A Comparison of Clarke's Completed Data Bases and Reiter's Closed World Assumption’, J. Logic Programming 1, 51–79 (1984).
J. Shepherdson, ‘Negation as Failure’, J. Logic Programming 2, 185–202 (1985).
J. Shepherdson, ‘Negation in Logic Programming’, in: Foundations of Deductive Databases and Logic Programming, (ed. J. Minker), Morgan Kaufmann 1987, pp. 19–88.
M. H.Van Emden and R. A. Kowalski, ‘The Semantics of Predicate Logic as a Programming Language’, J. ACM 3, 733–742 (1976).
A. Van Gelder, ‘Negation as Failure Using Tight Derivations for General Logic Programs’, in: Foundations of Deductive Databases and Logic Programming, (ed. J. Minker), Morgan Kaufmann 1987, pp. 149–176.
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Przymusinski, T.C. On the declarative and procedural semantics of logic programs. J Autom Reasoning 5, 167–205 (1989). https://doi.org/10.1007/BF00243002
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DOI: https://doi.org/10.1007/BF00243002