Discounting, time preference, and identity

There are many reasons to care less about (or "discount") future outcomes. I propose a conceptual framework for sorting through the distinct theoretical concepts which are often confounded in discussions of discounting and intertemporal choice. I emphasize the distinction between discounting a future consequence because it will confer less utility in the future and discounting future utility, per se. The normative legitimacy of discounting future utility is controversial. Many philosophers contend that there is no rational basis for it. However, some philosophers have defended the rationality of discounting utility by appealing to a complex view of personal identity. They argue that there is no enduring entity over time to whom future utility can be ascribed; that discounting one's "own" future utility is akin to discounting someone else's utility, because the separation between the temporal stages of one individual are as "deep" as the separation between individuals. I discuss this philosophical view on personal identity and its implications regarding the normative legitimacy of discounting future utility. I present an empirical study designed to help quantify the degree of discounting that might be justified by this philosophical perspective. The final chapter focuses on intergenerational tune preference, in the context of life-saving policies. Much of the prior research on intergenerational discount rates has concluded that people care much less about the welfare of future generations. However, the studies I present raise doubts about this conclusion.