Abstract

In this work I claim that practical reasoning aims at determining acts that would be all in all optimal to perform. This claim is taken to characterize practical reasoning in the same way that the claim that theoretical reasoning aims at determining true propositions characterizes theoretical reasoning. It is, in other words, not directly a claim about rationality. Rationality is a characteristic of beliefs and choices, rather than of propositions or, directly, of acts. ;A characterization of what it is for an act to be all in all optimal is developed. A particular act, to be performed by a particular agent, is all in all optimal only if it is one of the best acts that agent could perform, relative to all the facts, all evaluative factors and all the act's alternatives. Only acts which can be the subject of practical thinking are admitted as practical alternatives. ;Since it is here assumed that the value of an act is determined by the value of its consequences, it may seem obvious that an optimal act is an act which would have optimal consequences. This, however, need not be the case. Practical reasoning essentially involves the comparison of possible alternatives, some of which are not actually performed. Non-performed alternative acts, it will be argued, are vague. Therefore, each such act will be associated not with a single set of consequences it would have, but rather with a set of equally possible alternative outcomes it might have. I argue that there is no way to evaluate possible acts so that optimal acts must be acts associated exclusively with optimal outcomes. The fact that optimal acts may be acts that would have less than optimal consequences is attributed neither to human epistemological shortcomings, nor to physical indeterminism. It is instead attributed to human behavioral limitations, and to the apparently ineliminable vagueness associated with possible acts