CLASP: Integrating Term Subsumption Systems and Production Systems

Rules and frames are two knowledge representation schemes whose strengths and weakness are complementary to each other. Although several previous systems have attempted to integrate the two, few efforts have been made to incorporate the terminological knowledge of the frame-based systems into the rule-based paradigm. To achieve a deep integration of the two schemes, we have developed and implemented a CLASsification-based Production system (CLASP). This paper describes two major processes of CLASP: a semantic pattern matcher and a pattern classifier. The semantic pattern matcher extends the pattern matching capabilities of rule-based systems through the use of terminological knowledge. The pattern classifier enables the system to compute a rule'S specificity, which is useful for conflict resolution, based on the semantics of its left-hand side. The paradigm not only enhances the reasoning capabilities of rule-based systems, but also helps to reduce the cost of maintaining such systems because definitional knowledge is explicitly represented in a form that facilitates sharing and minimizes duplication of effort.