Online research in philosophy

In a recent article, Trenton Mericks argues that psychological continuity analyses (PC-analyses) of personal identity over time are incompatible with endurantism. We contend that if Merricks's argument is valid, a parallel argument establishes that PC-analyses of personal identity are incompatible with perdurantism; hence, the correct conclusion to draw is simply that such analyses are all necessarily false. However, we also show that there is good reason to doubt that Merricks's argument is valid.

If persons endure, personal identity cannot be analyzed in terms of psychological continuity. That is one conclusion defended in my "Endurance, Psychological Continuity, and the Importance of Personal Identity" (PPR, 1999). Rea and Silver (PPR, 2000) claim that my argument for that conclusion is sound only if a parallel argument is sound. The parallel argument concludes that if persons perdure, personal identity cannot be analyzed in terms of psychological continuity. In this paper, I show that Rea and Silver are mistaken. My argument is sound but the parallel argument is not.

This thesis gives an overview of the topic of personal identity from a philosophical viewpoint, describing both numerical and qualitative aspects. Reductionist approaches to numerical identity, such as the neo-Lockean psychological continuity theory of Derek Parfit or the physical criterion theory of Bernard Williams, are subject to a discussion. Apart from some significant criticisms in detail, there is the more general problem that they appear to imply a kind of neo-dualism. As a consequence, the author suggests a holistic approach to numerical personal identity which is more in accord with our times, placing the body firmly at the center of focus. The section on qualitative identity aims to develop a more complex theory of psychological continuity and continuity per se than that generally found in the literature. The suggestion is made that the most viable way to bring together the various strands of personal identity, both numerical and qualitative, is a concept of narrativity. Narratives are both indicative of and constitutive of personal identity.

In this article, I develop and defend a conception of psychological continuity that differs from the 'orthodox' conception in terms of overlapping chains of strongly connected mental states. By recognizing the importance of the (narrative) interrelatedness of qualitatively dissimilar mental contents, as well as the role of the body in psychological continuity, I argue, serious problems confronting the orthodox view can be solved.

This paper argues that if persons last over time by "enduring", then no analysis or reduction of personal identity over time in terms of any sort of psychological continuity can be correct. In other words, any analysis of personal identity over time in terms of psychological continuity entails that persons are four-dimensional and have temporal parts. The paper then shows that if we abandon psychological analyses of personal identity-as we must if persons endure-Parfit's argument for the claim that identity does not matter in survival is easily undermined. The paper then suggests that this offers support for the claim that persons endure. Along the way the paper tries to clarify the contrast between the doctrine that persons endure and its rival, four-dimensionalism.

Many theories of personal identity allow for the metaphysical possibility of fission. In 1981 Nozick proposed a theory of personal identity called ‘the closest continuer view’ (CCV) that denies fission in the case of persons but allows fisson in the case of human beings. CCV may thus appear to reduce ‘person’ to a nonmetaphysical, practical notion. Against this I argue that CCV is an externalist metaphysical theory that purports to solve a problem that is insurmountable within the confines of an internalist metaphysics of personal identity.

The view that an account of personal identity can be provided in terms of psychological continuity has come under fire from an interesting new angle in recent years. Critics from a variety of rival positions have argued that it cannot adequately explain what makes psychological states co-personal (i.e. the states of a single person). The suggestion is that there will inevitably be examples of states that it wrongly ascribes using only the causal connections available to it. In this paper, I describe three distinct attacks on the psychological continuity theory along these lines. While I acknowledge that a number of interesting issues arise, I argue that the theory can withstand all three attacks.