Components of Expertise

Over the past decade, it has become clear that one should go beyond the level of formalisms and programming constructs to understand and analyze expert systems. I discuss the idea of inference structures such as heuristic classification (Clancey 1985), the distinction between deep and surface knowledge (Steels 1984), the notion of problem-solving methods and domain knowledge filling roles required by the methods (McDermott 1988), and the idea of generic tasks and task-specific architectures (Chandrasekaran 1983). Such a synthesis is presented here in the form of a componential framework. The framework stresses modularity and consideration of the pragmatic constraints of the domain. A major question with knowledge engineering is (or should be) that given a particular task, how do we go about solving it using expert system techniques.