ParaLog e: a paraconsistent evidential logic programming language

Inconsistency is a natural phenomenon arising from the description of the real world. This phenomenon may be encountered in several situations. Nevertheless, human beings are capable of reasoning adequately. The automation of such reasoning requires the development of formal theories. ParaLog (Paraconsistent Logic) was proposed by N.C.A. da Costa et al. (1995) to provide tools to reason about inconsistencies. This paper describes an extension of the ParaLog logic programming language, called ParaLog e, that allows direct handling of inconsistency. Languages such as ParaLog e, which are capable of merging classical logic programming concepts with those of inconsistency, widen the scope of logic programming applications in environments presenting conflicting beliefs and contradictory information