No One Knows the Date or the Hour: An Unorthodox Application of Rev. Bayes's Theorem

Abstract

JSTOR is a not-for-profit service that helps scholars, researchers, and students discover, use, and build upon a wide range of content in a trusted digital archive. We use information technology and tools to increase productivity and facilitate new forms of scholarship. For more information about JSTOR, please contact support@jstor.org.. Carter and Leslie (1996) have argued, using Bayes's theorem, that our being alive now supports the hypothesis of an early 'Doomsday'. Unlike some critics (Eckhardt 1997), we accept their argument in part: given that we exist, our existence now indeed favors 'Doom sooner' over 'Doom later'. The very fact of our existence, however, favors 'Doom later'. In simple cases, a hypothetical approach to the problem of 'old evidence' shows that these two effects cancel out: our existence now yields no information about the coming of Doom. More complex cases suggest a move from countably additive to non-standard probability measures. The University of Chicago Press

Monty Hall, Doomsday and confirmation

“…For simplicity, and for the purposes of analogy with the Monty Hall problem, we have assumed that n is finite (and known). This assumption can be relaxed in a confirmation-theoretic rendition of the argument (see Bartha & Hitchcock 1999 for a confirmation-theoretic rendition that allows n to be infinite). This is another advantage of thinking about Doomsday confirmation-theoretically rather than posterior-probabilistically.…”

“…Interestingly, this is not how the Doomsday Argument is typically formulated (see, for instance, Bartha & Hitchcock 1999;Bostrom 2002;Korb & Oliver 1999;Leslie 1997;Sober 2002). The most sophisticated versions of the argument begin with (something tantamount to) the following different question about the Doomsday set-up.…”

Confirmation in a Branching World: The Everett Interpretation and Sleeping Beauty

“…Adam Elga 19 Those who accept that evidence for MWI is easy to come by might endorse the Self-Indication Assumption (Bostrom [2002]), which provides a priori confirmation of hypotheses with greater populations. Bostrom rejects it, but similar positions are defended by Bartha and Hitchcock ([1999]), Dieks ([2007]) and Peter Lewis ([2010]), who all claim that it cancels out the shift in favour of smaller populations of the Doomsday Argument. about selection effects that are not just false but incoherent -they require that the procedures are biased in both directions.…”

The Doomsday Argument and the Number of Possible Observers

“…The idea that one is more likely to find oneself in the long-lived race is called the SelfIndication Assumption by Bostrom. It was first discussed by Dieks [8], and has since been criticized by Leslie [3] and Bostrom [6] and defended by Kopf, Krtous and Page [9] and by Bartha and Hitchcock [10]. I will give several arguments in favor and attempt to answer Bostrom's and Leslie's objections.…”