Abstract

In this paper, I attempt to map out the 'logical geography' of the territory in which issues of mental content and of personal identity meet. In particular, I investigate the possibility of combining a psychological criterion of personal identity with an externalist theory of content. I argue that this can be done, but only by accepting an assumption that has been widely accepted but barely argued for, namely that when someone switches linguistic communities, the contents of their thoughts do not change immediately, but only after the person becomes integrated within the new linguistic community. I also suggest that recent work on personal identity, notably by Derek Parfit, has tacitly assumed internalism regarding mental content. I do not intend to argue for either externalism or a psychological criterion. My aim is merely to explicate the issues involved in making them compatible.