Many philosophers have become sceptical of the use of thought experiments in theorising about personal identity. In large part this is due to work in experimental philosophy that appears to confirm long held philosophical suspicions that thought experiments elicit inconsistent judgements about personal identity, and hence judgements that are thought to be the product of cognitive biases. If so, these judgements appear to be useless at informing our theories of personal identity. Using the methods of experimental philosophy, we investigate whether (...) people exhibit inconsistent judgements and, if they do, whether these judgements are likely to be the source of cognitive bias or, instead, sensitivity to some relevant factor. We do not find that people’s judgements are sensitive to any of the factors we investigate (relevant or irrelevant), nor that people have inconsistent judgements across cases. Rather, people’s judgements are best explained by them having a very minimal account of what it takes for a person to survive. Since this pattern of judgements is no reason to think that we are subject to cognitive bias, we see no reason, as things stand, to be sceptical of our judgements. (shrink)

Many philosophers are sympathetic to a perdurantist view of persistence. One challenge facing this view lies in its ability to ground prudential rationality. If, as many have thought, numerical identity over time is required to ground there being sui generis (i.e. non-instrumental) prudential reasons, then perdurantists can appeal only to instrumental reasons. The problem is that it is hard to see how, by appealing only to instrumental reasons, the perdurantist can vindicate the axiom of prudence: the axiom that any person-stage (...) has reason to promote the wellbeing of any other person-stage that is part of the same person as that stage. The claim that perdurantists cannot vindicate the axiom, and hence that the view should be rejected, is what we call the normative argument against perdurantism. In this paper we argue that purely instrumental rationality can ground the truth of this axiom, and hence that the normative argument against perdurantism fails. (shrink)