Changing minds in a changing world
I defend a general rule for updating beliefs that takes into account both the impact of new evidence and changes in the subject’s location. The rule combines standard conditioning with a “shifting” operation that moves the center of each doxastic possibility forward to the next point where information arrives. I show that well-known arguments for conditioning lead to this combination when centered information is taken into account. I also discuss how my proposal relates to other recent proposals, what results it delivers for puzzles like the Sleeping Beauty problem, and whether there are diachronic constraints on rational belief at all.
KeywordsBelief revision Update Conditionalisation Self-location Centered worlds
For helpful comments on earlier versions I would like to thank Jens Christian Bjerring, David Chalmers, John Cusbert, Alan Hájek, Namjoong Kim, Stephan Leuenberger, Weng Hong Tang, Michael Titelbaum, J. Robert G. Williams, two anonymous referees, and the audience of a PhilSoc seminar at the Australian National University in February 2008. Several points made in this paper, especially in Sect. 6, are also made in Meacham (2010), which appeared while this paper was under review.
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