# PP-2001-09: Characterization of Strongly Equivalent Logic Programs in Intermediate Logics

PP-2001-09: Hendriks, Lex and de Jongh, Dick (2001) Characterization of Strongly Equivalent Logic Programs in Intermediate Logics. [Report]

The non-classical, nonmonotonic inference relation associated with the stable model semantics for logic programs gives rise to a relationship of {\em strong equivalence} between logical programs that can be verified in the 3-valued G\"odel logic, {\bf G3}, the strongest non-classical intermediate propositional logic (see~\cite{lpv}). In this paper we will show that {\bf KC} (the logic of $\neg p\vee\neg\neg p$) is the weakest intermediate logic for which strongly equivalent logic programs in a language allowing negations are logically equivalent.