Building Knowledge-Based Systems: The PSN Experience

Knowledge-representation languages have been classified traditionally as declarative or procedural, depending on whether their basic features come from mathematical logic or data structures on one hand, or from programming languages on the other hand. Procedural representation languages are particularly well suited for heuristic knowledge, and their use can lead to efficient searching on the part of an expert system. Many attempts have been made to integrate features of declarative and procedural representation languages. PSN is one attempt that focuses on the integration of semantic network and procedural notions