Abstract

How can one knowingly choose against one's best judgment? This is both a traditional philosophical puzzle and a realistic problem in our everyday life. This dissertation is an exposition and examination of a recent work, by George Ainslie, with regard to its innovative explanation as well as rational solution of such a problem. With the help of the new Ainsliean model, I have also sought to offer some analysis of a number of issues that I believe are important to the understanding of the nature of practical rationality. ;The central question for Ainslie's approach to the dynamic problem of preference change is how to justify the "bundling" idea underlying his solution of the problem by adopting a "personal rule." The bundling idea is a belief in the relation between a series of similar choices as each predicting the direction of all the later choices. Being able to think in terms of this bundling idea is a powerful means of abstaining from defection, though it requires considerable cognitive effort. I try to defend the plausibility of such a personal-rule approach. But Ainslie's own account falls short of showing the ultimate necessity of the bundling idea, viz., why the collapse of the whole sequence of choices would necessarily follow from one defection. My argument hinges on demonstrating that neither a causal consideration about the links between similar choices, nor a prudential consideration about the possible risk involved in certain actions is sufficient for understanding the necessity: we need a normative perspective instead. ;This leads to my analysis of the conditions under which a normative solution can be justified. The analysis also delineates the type of dynamic choice situations Ainslie's approach may adequately fit, or have the greatest advantage. Some underlying hypothesis about the status and role of cognition in desire and higher-level motivation is carefully discussed; and the cognitive, deliberative, and affective aspects of the adoption of a rule is explored. During my discussions, I also compare Ainslie's approach with other theories in the domain of practical reasoning, such as that of Donald Davidson's, Jon Elster's, Michael Bratman's, Edward McClennen's, and David Gauthier's, in terms of their explanatory power, or their scope of application, limits, and complementarity. ;Ainslie's motivational model of mind has apparent as well as potential implications for a group of interesting philosophical issues. They include the nature of willpower, the nature of practical rationality as well as moral rules, personal identity, autonomy, and the existentialist theme on self-creation. My conclusion is that the clarification of the metaphysical underpinnings of the Ainsliean model can help to shed some light on these issues.