Agreeing to Disagree

  • Robert J. AumannEmail author
Part of the Springer Graduate Texts in Philosophy book series (SGTP, volume 1)


Two people, 1 and 2, are said to have common knowledge of an event E if both know it, 1 knows that 2 knows it, 2 knows that 1 knows it, 1 knows that 2 knows that 1 knows it, and so on.

Theorem If two people have the same priors, and their posteriors for an event A are common knowledge, then these posteriors are equal.



This work was supported by National Science Foundation Grant SOC74-11446 at the Institute for Mathematical Studies in the Social Sciences, Stanford University.


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Copyright information

© Springer International Publishing Switzerland 2016

Authors and Affiliations

  1. 1.Federmann Center for the Study of RationalityThe Hebrew University of JerusalemJerusalemIsrael

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