Theory and Decision

, Volume 73, Issue 4, pp 513–523 | Cite as

Reasoning-based introspection

Open Access


We show that if an agent reasons according to standard inference rules, the truth and introspection axioms extend from the set of non-epistemic propositions to the whole set of propositions. This implies that the usual axiomatization of partitional possibility correspondences is redundant, and provides a justification for truth and introspection that is partly based on reasoning.


Knowledge Introspection Truth axiom Partitional information structures Epistemic game theory 

JEL Classification

D80 D83 D89 



We are indebted to Geir Asheim, Giacomo Bonanno, Amanda Friedenberg, Willemien Kets, Friederike Mengel, Andrés Perea, Philippe Mongin, Mark Voorneveld, and Jörgen Weibull for fruitful discussions and useful comments. We would also like to thank the audiences of the Epistemic Game Theory Workshop (Stony Brook), Game Theory Conference (Stony Book), ESEM (Barcelona), SAET (Ischia), CRETE (Tinos), Bocconi University, LSE, Santa Fe Institute, Paris Game Theory Seminar, IHPST (Paris), Stockholm School of Economics, University of Warwick, HEC Lausanne, and Göteborg University. The financial support from the Marie Curie Intra-European Fellowship is gratefully acknowledged (PIEF-GA-2009-237614).

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.


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Copyright information

© The Author(s) 2011

Authors and Affiliations

  1. 1.Paris School of EconomicsParisFrance
  2. 2.London School of Economics and Political ScienceLondonUK
  3. 3.Maastricht UniversityMaastrichtThe Netherlands

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