The British Journal for the Philosophy of Science

Everettian Confirmation and Sleeping Beauty

Alastair Wilson

Published Sep 1, 2013• 25 citations

Abstract

Darren Bradley has recently appealed to observation selection effects to argue that conditionalization presents no special problem for Everettian quantum mechanics, and to defend the ‘halfer’ answer to the puzzle of Sleeping Beauty. I assess Bradley’s arguments and conclude that while he is right about confirmation in Everettian quantum mechanics, he is wrong about Sleeping Beauty. This result is doubly good news for Everettians: they can endorse Bayesian confirmation theory without qualification, but they are not thereby compelled to adopt the unpopular ‘halfer’ answer in Sleeping Beauty. These considerations suggest that objective chance is playing an important and under-appreciated role in Sleeping Beauty. 1 Introduction 2 Confirmation in Everettian Quantum Mechanics 3 Sleeping Beauty 4 The Selection Model 5 Bradley’s Argument 6 The Right Route to ⅓ 7 The Breakdown of the Analogy 8 Alternative Diagnoses 9 God’s Gambling Game 10 Non-chancy Sleeping Beauty Cases 11 Conclusion

DOI: 10.1093/bjps/axt018

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