Towards a Systematic Account of Different Semantics for Logic Programs

Abstract

A new methodology has been proposed which allows one to derive uniform characterizations of different declarative semantics for logic programs with negation. One result from this work is that the well-founded semantics can formally be understood as a stratified version of the Fitting (or Kripke–Kleene) semantics. The constructions leading to this result, however, show a certain asymmetry which is not readily understood. We study this situation here with the result that we obtain a coherent picture of relations between different semantics for normal logic programs