Practical rationality and the limits of instrumentalism

Abstract

I show Means/end or "instrumental" models of practical rationality maintain that an agent is rational if she is taking efficient means to secure her most important ends. According to this view, an agent's goals are not themselves open to rational assessment. Only the efficiency of means to chosen ends is evaluated. These accounts raise an important question in contemporary debates about practical rationality: whether a complete theory of practical rationality must include a theory of value (a theory by which ends are evaluated to determine whether they are rational). After placing various means/end accounts in historical perspective and illustrating their contemporary significance, I defend a negative answer to the above question and thus embrace a form of instrumentalism. I show that certain arguments concerning the rationality of final ends are reducible to arguments about other matters pertaining to things being constituents of ends or means to final ends. Moreover, examples of irrational desires designed to show that means/end conceptions are inadequate simply appeal to our intuitions and many will not share those intuitions in all cases. The intuitive appeal of instrumental theories will be bolstered if it is emphasized that they do not permit the pursuit of every fleeting desire, but rather those which the agent herself deems most important. There are no sufficient grounds for a rejection of instrumentalism. Attempts at alternative views either collapse into instrumentalist accounts or they fail to provide the principles needed to establish a satisfactory account of rationality applicable to all agents.