, Volume 196, Issue 1, pp 399–412 | Cite as

A-symmetric confirmation and anthropic skepticism

  • Benjamin EvaEmail author


In recent years, anthropic reasoning has been used to justify a number of controversial skeptical hypotheses (both scientific and philosophical). In this paper, we consider two prominent examples, viz. Bostrom’s ‘Simulation Argument’ and the problem of ‘Boltzmann Brains’ in big bang cosmology. We argue that these cases call into question the assumption, central to Bayesian confirmation theory, that the relation of evidential confirmation is universally symmetric. We go on to argue that the fact that these arguments appear to contradict this fundamental assumption should not be taken as an immediate refutation, but should rather be seen as indicative of the peculiar role that the relevant hypotheses play in their respective epistemic frameworks.



This work was generously supported by the Ludwig Maximilian University Center for Advanced Studies. I’d also like to thank John Norton and three anonymous referees for their helpful comments on earlier versions of the paper.


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© Springer Nature B.V. 2017

Authors and Affiliations

  1. 1.Munich Center for Mathematical PhilosophyLMU MunichMunichGermany

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