pp 1–21 | Cite as

The joint aggregation of beliefs and degrees of belief

  • Paul D. Thorn


The article proceeds upon the assumption that the beliefs and degrees of belief of rational agents satisfy a number of constraints, including: (1) consistency and deductive closure for belief sets, (2) conformity to the axioms of probability for degrees of belief, and (3) the Lockean Thesis concerning the relationship between belief and degree of belief. Assuming that the beliefs and degrees of belief of both individuals and collectives satisfy the preceding three constraints, I discuss what further constraints may be imposed on the aggregation of beliefs and degrees of belief. Some possibility and impossibility results are presented. The possibility results suggest that the three proposed rationality constraints are compatible with reasonable aggregation procedures for belief and degree of belief.


Belief aggregation Opinion pooling Discursive dilemma Full and partial belief The Lockean thesis 



Work on this paper was supported by the DFG Grant SCHU1566/9-1 as part of the priority program New Frameworks of Rationality (SPP 1516), and by the DFG Collaborative Research Centre 991: The Structure of Representations in Language, Cognition, and Science. For valuable comments and suggestions I am thankful to Peter Brössel, Ludwig Fahrbach, Theo Kuipers, Olivier Roy, Gerhard Schurz, and two anonymous reviewers for Synthese. I particularly indebted to the contributions of Christian Feldbacher-Escamilla, who came up with the idea to investigate the synchronized aggregation of beliefs and degrees of belief, and provided many valuable suggestions during conversations of this topic.


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© Springer Nature B.V. 2018

Authors and Affiliations

  1. 1.Heinrich Heine Universitaet DuesseldorfDuesseldorfGermany

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