Belief dependence: How do the numbers count?
This paper is about how to aggregate outside opinion. If two experts are on one side of an issue, while three experts are on the other side, what should a non-expert believe? Certainly, the non-expert should take into account more than just the numbers. But which other factors are relevant, and why? According to the view developed here, one important factor is whether the experts should have been expected, in advance, to reach the same conclusion. When the agreement of two (or of twenty) thinkers can be predicted with certainty in advance, their shared belief is worth only as much as one of their beliefs would be worth alone. This expectational model of belief dependence can be applied whether we think in terms of credences or in terms of all-or-nothing beliefs.
KeywordsEpistemology Social epistemology Belief dependence Disagreement
For helpful advice, I’m grateful to an anonymous reviewer at Philosophical Studies, Nomy Arpaly, Anna Brinkerhoff, Jamie Dreier, Nina Emery, Dave Estlund, Arianna Falbo, Tobias Fuchs, Kelly Gaus, Yongming Han, Rachel Leadon, Nick Leonard, Han Li, Chad Marxen, Adam Pautz, Justin Pombrio, Brett Topey, Leo Yan, and members of the Dissertation Workshop at Brown University. Special thanks to Josh Schechter and David Christensen.
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