If one can get the targets of one's current wants only by acquiring new wants (as in the Prisoner's Dilemma), is it rational to do so? Arguably not. For this could justify adopting unsatisfiable wants, violating the rational duty to maximize one's utility. Further, why cause a want's target if one will not then want it? And people "are" their wants. So if these change, people will not survive to enjoy their wants' targets. I reply that one rationally need not advance one's future wants, only current ones. Furthermore, rational choice seeks not utility (the co-obtaining of a want and its target), but satisfaction (the eventual obtaining of what is now wanted) -- otherwise, it would be irrational to care now about what happens after one dies. Finally, persons survive "rational" changes of values. Thus reflection on the rational revision of values illuminates the conditions on personal identity and the bases and aims of rational choice.