Charles J. Petrie, Jr.
Traditional applications of "Truth Maintenance Systems"(TMSs) fail to adequately represent heuristic search in which some paths are initially preferred. What they miss is the idea of switching contexts rationally based on heuristic preferences. We show that it is useful, especially for plans with contingencies, to maintain the validity of the reason for context choices and rejections. We demonstrate how to do so with a problem solver/TMS architecture called REDUX.