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Logic Programming and Knowledge Representation
 Journal of Logic Programming
, 1994
"... In this paper, we review recent work aimed at the application of declarative logic programming to knowledge representation in artificial intelligence. We consider exten sions of the language of definite logic programs by classical (strong) negation, disjunc tion, and some modal operators and sh ..."
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Cited by 234 (20 self)
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In this paper, we review recent work aimed at the application of declarative logic programming to knowledge representation in artificial intelligence. We consider exten sions of the language of definite logic programs by classical (strong) negation, disjunc tion, and some modal operators and show how each of the added features extends the representational power of the language.
Fixpoint semantics for logic programming  a survey
, 2000
"... The variety of semantical approaches that have been invented for logic programs is quite broad, drawing on classical and manyvalued logic, lattice theory, game theory, and topology. One source of this richness is the inherent nonmonotonicity of its negation, something that does not have close para ..."
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Cited by 126 (0 self)
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The variety of semantical approaches that have been invented for logic programs is quite broad, drawing on classical and manyvalued logic, lattice theory, game theory, and topology. One source of this richness is the inherent nonmonotonicity of its negation, something that does not have close parallels with the machinery of other programming paradigms. Nonetheless, much of the work on logic programming semantics seems to exist side by side with similar work done for imperative and functional programming, with relatively minimal contact between communities. In this paper we summarize one variety of approaches to the semantics of logic programs: that based on fixpoint theory. We do not attempt to cover much beyond this single area, which is already remarkably fruitful. We hope readers will see parallels with, and the divergences from the better known fixpoint treatments developed for other programming methodologies.
A Logical Semantics For Hypothetical Rulebases With Deletion
, 1997
"... This paper addresses a limitation of most deductive database systems: they ..."
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Cited by 6 (2 self)
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This paper addresses a limitation of most deductive database systems: they
Intuitionistic Deductive Databases And The Polynomial Time Hierarchy
, 1997
"... this paper, we establish more comprehensive results by exploring the interaction of negationasfailure with a natural syntactic restriction called linearity. The main result is a tight connection between intuitionistic logic, database queries, and the polynomial time hierarchy. A tight connection w ..."
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Cited by 5 (2 self)
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this paper, we establish more comprehensive results by exploring the interaction of negationasfailure with a natural syntactic restriction called linearity. The main result is a tight connection between intuitionistic logic, database queries, and the polynomial time hierarchy. A tight connection with secondorder logic follows as a corollary. First, we show that rulebases in our language fit neatly into a wellestablished logical frameworkintuitionistic logic. Second, we show that linearity reduces their data complexity from PSPACE to NP. Third, we show that negationasfailure increases their complexity from NP to some level in the polynomial time hierarchy (PHIER). Specifically, linear rulebases with k strata are data complete for \Sigma
Hypothetical Reasoning with Intuitionistic Logic
 NonStandard Queries and Answers, Studies on Logic and Computation, chapter 8
, 1994
"... This paper addresses a limitation of most deductive database systems: They cannot reason hypothetically. Although they reason effectively about the world as it is, they are poor at tasks such as planning and design, where one must explore the consequences of hypothetical actions and possibilities. T ..."
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Cited by 5 (4 self)
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This paper addresses a limitation of most deductive database systems: They cannot reason hypothetically. Although they reason effectively about the world as it is, they are poor at tasks such as planning and design, where one must explore the consequences of hypothetical actions and possibilities. To address this limitation, this paper presents a logicprogramming language in which a user can create hypotheses and draw inferences from them. Two types of hypothetical operations are considered: the insertion of tuples into a database, and the creation of new constant symbols. These two operations are interesting, not only because they extend the capabilities of database systems, but also because they fit neatly into a wellestablished logical framework, namely intuitionistic logic. This paper presents the proof theory for the logic, outlines its intuitionistic model theory, and summarizes results on its complexity and on its ability to express database queries. Our results establish a st...
Hypothetical updates, priority and inconsistency in a logic programming language
 In Proc. of the Third Int. Conference on Logic Programming and Nonmonotonic Reasoning, volume 928 of LNAI
, 1995
"... Abstract. In this paper we propose a logic programming language which supports hypothetical updates together with integrity constraints. The language allows sequences of updates by sets of atoms and it makes use of a revision mechanism to restore consistency when an update violates some integrity co ..."
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Cited by 4 (1 self)
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Abstract. In this paper we propose a logic programming language which supports hypothetical updates together with integrity constraints. The language allows sequences of updates by sets of atoms and it makes use of a revision mechanism to restore consistency when an update violates some integrity constraint. The revision policy we adopt is based on the simple idea that more recent information is preferred to earlier one. This language can be used to perform several types of defeasihle reasoning. We define a goaldirected proof procedure for the language and develope a logical characterization in a modal logic by introducing an abductive semantics. 1
On Prudent Bravery and Other Abstractions
 In preparation
, 1994
"... ions Melvin Fitting fitting@alpha.lehman.cuny.edu Dept. Mathematics and Computer Science Lehman College (CUNY), Bronx, NY 10468 Depts. Computer Science, Philosophy, Mathematics Graduate Center (CUNY), 33 West 42nd Street, NYC, NY 10036 # October 13, 1994 Abstract A special class of partial ..."
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Cited by 3 (2 self)
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ions Melvin Fitting fitting@alpha.lehman.cuny.edu Dept. Mathematics and Computer Science Lehman College (CUNY), Bronx, NY 10468 Depts. Computer Science, Philosophy, Mathematics Graduate Center (CUNY), 33 West 42nd Street, NYC, NY 10036 # October 13, 1994 Abstract A special class of partial stable models, the intrinsic ones, is singled out for consideration, and attention is drawn to the largest one, which we designate as the prudently brave one. It is the largest partial stable model that is compatible with every partial stable model. As such, it is an object of natural interest. Its existence follows from general properties of monotonic functions, so it is a robust notion. The proofs given concerning intrinsic stable models are not new, but they appeared earlier in quite di#erent contexts. What we do, essentially, is call the attention of the logic programming and nonmonotonic reasoning community to them. We further show the entire development fits into the bilattice ...
www.elsevier.com/locate/tcs Fixpoint semantics for logic programming a survey
"... The variety of semantical approaches that have been invented for logic programs is quite broad, drawing on classical and manyvalued logic, lattice theory, game theory, and topology. One source of this richness is the inherent nonmonotonicity of its negation, something that does not have close para ..."
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The variety of semantical approaches that have been invented for logic programs is quite broad, drawing on classical and manyvalued logic, lattice theory, game theory, and topology. One source of this richness is the inherent nonmonotonicity of its negation, something that does not have close parallels with the machinery of other programming paradigms. Nonetheless, much of the work on logic programming semantics seems to exist side by side with similar work done for imperative and functional programming, with relatively minimal contact between communities. In this paper we summarize one variety of approaches to the semantics of logic programs: that based on 0xpoint theory. We do not attempt to cover much beyond this single area, which is already remarkably fruitful. We hope readers will see parallels with, and the divergences from the better known 0xpoint treatments developed for other programming methodologies. c © 2002 Elsevier Science B.V. All rights reserved. 1.