Extending Description Logic Rules?

Abstract. Description Logics – the logics underpinning the Web On-tology Language OWL – and rules are currently the most prominent paradigms used for modeling knowledge for the Semantic Web. While both of these approaches are based on classical logic, the paradigms also differ significantly, so that naive combinations result in undesirable prop-erties such as undecidability. Recent work has shown that many rules can in fact be expressed in OWL. In this paper we extend this work to in-clude some types of rules previously excluded. We formally define a set of first order logic rules, C-Rules, which can be expressed within OWL extended with role conjunction. We also show that the use of nominal schemas results in even broader coverage.