Judgment aggregation and the problem of tracking the truth

Abstract

The aggregation of consistent individual judgments on logically interconnected propositions into a collective judgment on those propositions has recently drawn much attention. Seemingly reasonable aggregation procedures, such as propositionwise majority voting, cannot ensure an equally consistent collective conclusion. In this paper, we motivate that quite often, we do not only want to make a factually right decision, but also to correctly evaluate the reasons for that decision. In other words, we address the problem of tracking the truth. We set up a probabilistic model that generalizes the analysis of Bovens and Rabinowicz (Synthese 150: 131–153, 2006) and use it to compare several aggregation procedures. Demanding some reasonable adequacy constraints, we demonstrate that a reasons- or premise-based aggregation procedure tracks the truth better than any other procedure. However, we also illuminate that such a procedure is not in all circumstances easy to implement, leaving actual decision-makers with a tradeoff problem.

References

  1. Bovens L., Rabinowicz W. (2006) Democratic answers to complex questions. An epistemic perspective. Synthese 150: 131–153

    Article  Google Scholar 

  2. Dietrich F., List C. (2006) Arrow’s theorem in judgment aggregation. Social Choice and Welfare 29(1): 19–33

    Article  Google Scholar 

  3. Dietrich F., Mongin P. (2010) The premiss-based approach to judgment aggregation. Journal of Economic Theory 145(2): 562–582

    Article  Google Scholar 

  4. Hartmann S., Pigozzi G., Sprenger J. (2010) Reliable methods of judgment aggregation. Journal for Logic and Computation 20(2): 603–617

    Article  Google Scholar 

  5. List C. (2005) The probability of inconsistencies in complex collective decisions. Social Choice and Welfare 24(1): 3–32

    Article  Google Scholar 

  6. List C. (2006) The discursive dilemma and public reason. Ethics 116(2): 362–402

    Article  Google Scholar 

  7. List, C. (2007). Judgment aggregation—a bibliography on the discursive dilemma, the doctrinal paradox and decisions on multiple propositions. http://personal.lse.ac.uk/LIST/doctrinalparadox.htm.

  8. List C., Pettit P. (2002) Aggregating sets of judgments: An impossibility result. Economics and Philosophy 18: 89–110

    Google Scholar 

  9. Miller M. K., Osherson D. (2009) Methods for distance-based judgment aggregation. Social Choice and Welfare 32: 575–601

    Article  Google Scholar 

  10. Mongin P. (2008) Factoring out the impossibility of logical aggregation. Journal of Economic Theory 141: 100–113

    Article  Google Scholar 

  11. Mongin, P. (2011). The doctrinal paradox, the discursive dilemma, and logical aggregation theory. Theory and Decision (Forthcoming).

  12. Nozick R. (1981) Philosophical Explanations. Harvard University Press, Harvard

    Google Scholar 

  13. Pigozzi G. (2006) Belief merging and the discursive dilemma: an argument-based account to paradoxes of judgment aggregation. Synthese 152(2): 285–298

    Article  Google Scholar 

Download references

Acknowledgments

We thank Horacio Arlo-Costa for his kind invitation to submit to this issue of Synthese, and Thomas Grundmann, Carlo Martini, Philippe Mongin, Gabriella Pigozzi and an anonymous referee for their helpful feedback. Research on this project was supported by the Veni Grant 016.104.079 ‘An Objective Guide for Public Policy’ by the Netherlands Organisation for Scientific Research (NWO).

Open Access

This article is distributed under the terms of the Creative Commons Attribution Noncommercial License which permits any noncommercial use, distribution, and reproduction in any medium, provided the original author(s) and source are credited.

Author information

Affiliations

Authors

Corresponding author

Correspondence to Stephan Hartmann.

Rights and permissions

Open Access This is an open access article distributed under the terms of the Creative Commons Attribution Noncommercial License (https://creativecommons.org/licenses/by-nc/2.0), which permits any noncommercial use, distribution, and reproduction in any medium, provided the original author(s) and source are credited.

Reprints and Permissions

About this article

Cite this article

Hartmann, S., Sprenger, J. Judgment aggregation and the problem of tracking the truth. Synthese 187, 209–221 (2012). https://doi.org/10.1007/s11229-011-0031-5

Download citation

Keywords

  • Judgment aggregation
  • Truth-tracking
  • Discursive dilemma
  • Reasons
  • Justification