Abstract

Three extensions of the standard Prolog fixpoint semantics are presented (called sat, strong, and weak), using partial models, models which may fail to assign truth values to all formulas. Each of these semantics takes negation and quantification into account. All thee are conservative: they agree with the conventional semantics on pure Horn clause programs. The sat and the strong semantics incorporate the domain closure assumption, but differ on whether to assign a truth value to a classically valid formula some part of which lacks a truth value. The weak semantics is similar to the strong semantics but abandons the domain closure condition, and consequently, all programs give rise to continuous operators in this semantics. For the weak semantics, a sound and complete proof procedure is given, based on semantics tableaus (or equivalently, Gentzen Sequents).

Full Text
Paper version not known

Talk to us

Join us for a 30 min session where you can share your feedback and ask us any queries you have

Schedule a call

Disclaimer: All third-party content on this website/platform is and will remain the property of their respective owners and is provided on "as is" basis without any warranties, express or implied. Use of third-party content does not indicate any affiliation, sponsorship with or endorsement by them. Any references to third-party content is to identify the corresponding services and shall be considered fair use under The CopyrightLaw.