Another failed refutation of scepticism

Jessica Wilson has recently offered a more sophisticated version of the self-defeat objection to Cartesian scepticism. She argues that the assertion of Cartesian scepticism results in an unstable vicious regress. The way out of the regress is to not engage with the Cartesian sceptic at all, to stop the regress before it starts, at the warranted assertion that the external world exists. We offer three reasons why this objection fails: first, the sceptic need not accept Wilson’s characterization of the sceptical thesis and thus need not start her regress; second, even if she did commit to the regress, it would not undermine scepticism in the way Wilson envisages; and third, the appeal to mental state scepticism which is necessary to generate the second and subsequent steps in the regress is not justified.