How can we insure that knowledge embedded in a program is applied effectively? Traditionally the answer to this question has been sought in different problem solving paradigms and in different approaches to encoding and indexing knowledge. Each of these is…

Freud's theory of jokes explains how they overcome the mental "censors" that make it hard for us to think "forbidden" thoughts. But his theory did not work so well for humorous nonsense as for other comical subjects. In this essay…

We propose a vision of the structure of knowledge and processes of learning based upon the particularity of experience. Highly specific cognitive structures are constructed through activities in limited domains of experience. For new domains, new cognitive structures develop from…

This report describes a system which maintains canonical expressions for designators under a set of equalities. Substitution is used to maintain all knowledge in terms of these canonical expressions. A partial order on designators, termed the better-name relation, is used…

The object oriented programming style used in the Smalltalk and Actor languages is available in Lisp Machine Lisp, and used by the Lisp Machine software system. It is used to perform generic operations on objects. Part of its implementation is…

The goal of the commodity expert project was to develop a prototype program that would act as an intelligent assistant to a commodity market analyst. Since expert analysis must deal with very large, yet incomplete, data bases of unreliable facts…