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Title: Founded semantics and constraint semantics of logic rules
Abstract Logic rules and inference are fundamental in computer science and have been studied extensively. However, prior semantics of logic languages can have subtle implications and can disagree significantly, on even very simple programs, including in attempting to solve the well-known Russell’s paradox. These semantics are often non-intuitive and hard-to-understand when unrestricted negation is used in recursion. This paper describes a simple new semantics for logic rules, founded semantics, and its straightforward extension to another simple new semantics, constraint semantics, that unify the core of different prior semantics. The new semantics support unrestricted negation, as well as unrestricted existential and universal quantifications. They are uniquely expressive and intuitive by allowing assumptions about the predicates, rules and reasoning to be specified explicitly, as simple and precise binary choices. They are completely declarative and relate cleanly to prior semantics. In addition, founded semantics can be computed in linear time in the size of the ground program.  more » « less
Award ID(s):
1954837 1414078 1421893 1248184 0613913 0964196 1447549
PAR ID:
10232411
Author(s) / Creator(s):
;
Date Published:
Journal Name:
Journal of Logic and Computation
Volume:
30
Issue:
8
ISSN:
0955-792X
Page Range / eLocation ID:
1609 to 1668
Format(s):
Medium: X
Sponsoring Org:
National Science Foundation
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