Parfit, personal identity, and what matters

Abstract

The problem of personal identity has vexed philosophers since its initial formulation by John Locke. He argued that "person" is a distinct ontological entity' y from "man." In so doing, he initiated a separation of the physical and psychological which nearly all later philosophers follow. Some, unsatisfied by Locke's preference for the psychological, argue that physicality is the essential feature of personhood. Others, more inclined to support Locke, argue that psychology is the essential feature. A large portion of the discussion concerning the problem of personal identity is the dispute between these two opposing branches. Yet, despite their differences, both branches share a common goal: the search for necessary and sufficient conditions for personal identity, the search for a suitable "criterion." Derek Parfit, however, questions the primary motivation behind this quest. His arguments attempt to demonstrate not only that no such necessary and sufficient conditions exist, but that this conclusion is untroubling because identity is not even what matters in survival. This last suggestion-that identity is not what matters-is Parfit's novel contribution, and it is the suggestion with which this thesis is mostly concerned. My first task is a description of Parfit's arguments that lead to his radical conclusion. This includes an explication of his Spectra and Fission Arguments, each of which are then assessed. The second task is a description and evaluation of Parfit's replacement for identity, relation R. I examine the critical notion of "quasi" psychology and attack it on two grounds. First, I argue that it is not entirely clear that Parfit's description eliminates the necessity of personal identity: quasi-memory itself presupposes identity. Second, I argue that even if quasi-memory avoids circularity, it cannot matter in the way in which Parfit hopes it can. This is so, I suggest, because memories matter only because of their essential uniqueness. When this element is erased-as it is in quasi-memory memory" ceases to matter altogether. By way of concluding, I offer a hypothesis that illuminates not only Parfit's possible motivations, but his reasons for going awry.