USING PREDICATE LOGIC TO INTEGRATE QUALITATIVE REASONING AND CLASSICAL DECISION-THEORY

Classical decision theory can be very restrictive when formulating decision models for practical situations. The principal group of restrictions, inherent in numerical decision theories, is that they make no provision for reasoning about the decision process itself. Classical procedures cannot reflect on what the decision is, what the options are, what methods may be used in making a decision, what knowledge may be relevant, and so forth. An approach that accommodates classical decision theory within a framework of first-order logic with nonmonotonic extensions is described. Among the benefits offered by the approach are: the potential to express qualitative arguments about the desirability of decision options in the absence of probability or utility parameters; to automate techniques for generating decision options; and to initiate, control, and terminate a decision process autonomously. The rationality of a logical decision framework is discussed. A particular benefit of implementing decision procedures in a nonmonotonic logic is that decision systems can adapt automatically as beliefs change, contradictions are encountered, or new knowledge is acquired. © 1990 IEEE