 One can ascertain here all too well the inherent difficulties in thinking about personal identity and the limited benefit some thought experiments might have for what is deemed the proper metaphysics of personal identity. Nevertheless, good reasons have been given in favour of the use of thought experiments about personal identity (see Beck 2006; Kolak 1993; Hershenov 2008). We also feel that the problems about thought experiments on personal identity reveal more about the intricate nature of the subject than about the usefulness of philosophical thought experiments. And, disregarding other shortcomings in Wilkes’ skepticism (for further discussion of Wilkes’ views see Beck 1992; Brooks 1994; Focquaert 2003; Häggqvist 1996, pp. 27–34), her suggestion that thought experimental scenarios would have to satisfy current scientific knowledge about the relevant entities featured in a thought experiment is highly implausible. We learn a great deal about the world and our theories when we wonder, for instance, what would have happened after the big bang if the law of gravity had been an inverse cube law instead of an inverse square. Would stars have failed to form? Reasoning about such a scenario is perfectly coherent and very instructive, even though it violates a law of nature.