The Normative Implications of Personal Identity Theory

This dissertation investigates the relationship between personal identity theory and normative ethics. There are a surprising number of contradictory arguments about the relevance of personal identity criteria for ethics and political philosophy. For example, writers like David Gauthier, Thomas Nagel and John Rawls argue that utilitarianism disregards the separateness, or non-identity, of persons. Derek Parfit claims the opposite. According to him, utilitarians respect the separateness of persons while also respecting the disintegration within lives. Also, Henry Sidgwick was under the impression that the separateness of persons supports egoism and disregard for the other-regarding demands of morality. David Brink claims the opposite. According to him, the resulting form of egoism would be nearly indistinguishable from altruism and therefore not at odds with the other-regarding demands of morality. Finally, both Rawls and Nozick argue that the separateness of persons speaks in favour of their own deontological view—despite the fact that their views are fundamentally opposed. Rawls hopes to gain support for his contractually derived principles of justice, while Nozick believes he can generate support for his deontological side constraints. This situation is rather surprising and in need of an explanation. Finally, there have also been skeptical arguments about the force of such appeals, such as Rawls’s claims that personal identity theory and ethics are independent, and his claim that personal identity criteria are inherently normative. This dissertation looks at these controversies in detail and comes to the conclusion that the force of appeals to personal identity is considerably more fine-grained and more complex than has been presumed.Ph