An Assessment ofTools for Building Large Knowledge-Based Systems

At a minimum, commercial knowledge engineering tools support the use of rules for knowledge representation. In addition, tools designed for large KBSs also provide other knowledge representation approaches, such as frames, objects, and the ability to extend the knowledge base to support hypothetical reasoning. Rules Rules provide a modular and uniform approach to knowledge representation. Tools that support rules as their sole representation paradigm are relatively simple to learn and use. As rule-based systems grow, however, they become increasingly difficult to understand and maintain (van de Brug, Bachant, and McDermott 1986).