Abstract

This paper starts from the debate between proponents of a neo-Lockean psychological continuity view of personal identity, and defenders of the idea that we are simple mental substances. Each party has valid criticisms of the other; the impasse in the debate is traced to the Lockean assumption that substance is only externally related to its attributes. This suggests the possibility that we could develop a better account of mental substance if we thought of it as having an internal relation to its states. I suggest that we may be able to do this by relying on the notion of expression. In developing this idea I draw heavily on aspects of Wittgenstein's philosophical psychology, while also developing and criticizing Strawson's account of persons and recent work by Lynne Baker. I conclude by arguing that mental substance, understood in this way, can only be grasped in narrative terms; substantialist and narrative accounts of personal identity, far from being opposed, are mutually supporting and require one another to be coherent