Cautiously Approaching SWRL

Abstract

The Semantic Web Rules Language (SWRL) has recently been proposed as the basic rules language for the Semantic Web. SWRL is unusual in being an undecidable superset of a very expressive description logic - OWL DL (SHOIN(D)) and a simple rules language, Datalog. In this paper, we attempt to evolve OWL DL toward SWRL, but cautiously and carefully. We strive to retain practical decidability. We seek to meet identifiable needs as simply as possible. We also attempt to make use of existing work on integrating rules systems, especially Datalog, with expressive description logics. We want to build a rules system that people with a large commitment to OWL will find understandable and useful. With such an aim, we explore different ways to give the users what they want, while staying “close” to OWL, and “cautiously far” from the full expressivity of SWRL.