Jeffrey Sanford Russell, John Hawthorne, Lara Buchak

Research output: Contribution to journalArticlepeer-review

26 Scopus citations


How should a group with different opinions (but the same values) make decisions? In a Bayesian setting, the natural question is how to aggregate credences: how to use a single credence function to naturally represent a collection of different credence functions. An extension of the standard Dutch-book arguments that apply to individual decision-makers recommends that group credences should be updated by conditionalization. This imposes a constraint on what aggregation rules can be like. Taking conditionalization as a basic constraint, we gather lessons from the established work on credence aggregation, and extend this work with two new impossibility results. We then explore contrasting features of two kinds of rules that satisfy the constraints we articulate: one kind uses fixed prior credences, and the other uses geometric averaging, as opposed to arithmetic averaging. We also prove a new characterisation result for geometric averaging. Finally we consider applications to neighboring philosophical issues, including the epistemology of disagreement.

Original languageEnglish (US)
Pages (from-to)1287-1309
Number of pages23
JournalPhilosophical Studies
Issue number5
StatePublished - May 1 2015
Externally publishedYes

All Science Journal Classification (ASJC) codes

  • Philosophy


  • Conditionalization
  • Credence aggregation
  • Disagreement
  • Formal epistemology
  • Social epistemology


Dive into the research topics of 'Groupthink'. Together they form a unique fingerprint.

Cite this