Epistemic Foundation of the Well-Founded Semantics over Bilattices

We define new, both model-theoretical and fixpoint-based, characterizations of the well-founded semantics for logic programs in the general setting of bilattices. This work lights the role of the CWA, used in the well-founded semantics as a carrier of falsehood, and shows that the definition of that semantics does not require any separation of positive and negative information nor any program transformation.