Reference: Feigenbaum, E. A. Expert Systems: Principles and Practice. 1992.
Abstract: Most applications of the Artificial Intelligence (AI) science and technology are a type called Expert Systems. An Expert System (ES) is a computer program that reasons using knowledge to solve complex problems. This overly brief caricature will be expanded upon below, but it serves to indicate an alignment of ES with AI's long term goals. Traditionally, computers solve complex problems by arithmetic calculation (not by reasoning using logic); and the knowledge needed to solve the problem ins known only by the human programmer and used to cast the solution method in terms of algebraic formulas.
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