Philosophical Studies

, Volume 176, Issue 2, pp 297–319 | Cite as

Belief dependence: How do the numbers count?

  • Zach BarnettEmail author


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.


Epistemology 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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Copyright information

© Springer Science+Business Media B.V., part of Springer Nature 2017

Authors and Affiliations

  1. 1.Brown UniversityProvidenceUSA

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