Problem-solving with diagrammatic representations

摘要

Diagrams are of substantial benefit to WHISPER, a computer problem-solving system, in testing the stability of a “blocks world” structure and predicting the event sequences which occur as that structure collapses. WHISPER's components include a high level reasoner which knows some qualitative aspects of Physics, a simulated parallel processing “retina” to “look at” its diagrams, and a set of re-drawing procedures for modifying these diagrams. Roughly modelled after the human eye, WHISPER's retina can fixate at any diagram location, and its resolution decreases away from its center. Diagrams enable WHISPER to work with objects of arbitrary shape, detect collisions and other motion discontinuities, discover coincidental alignments, and easily update its world model after a state change. A theoretical analysis is made of the role of diagrams interacting with a general deductive mechanism such as WHISPER's high level reasoner.