Knowledge acquisition in rule-based systems: knowledge about representation as a basis for system construction and maintenance

Recent research efforts aimed at task-oriented systems have emphasized the importance of large stores of domainspecific knowledge as a basis for high performance. But assembling the required knowledge base is a difficult task that often extends over several years, and involves numerous modifications to the knowledge base. Given the difficulty of making even srnall changes to a program, this presents a challenging problem in system construction.