, Volume 184, Issue 1, pp 73–87 | Cite as

Walter the banker: the conjunction fallacy reconsidered

  • Stephan Hartmann
  • Wouter Meijs
Open Access


In a famous experiment by Tversky and Kahneman (Psychol Rev 90:293–315, 1983), featuring Linda the bank teller, the participants assign a higher probability to a conjunction of propositions than to one of the conjuncts, thereby seemingly committing a probabilistic fallacy. In this paper, we discuss a slightly different example featuring someone named Walter, who also happens to work at a bank, and argue that, in this example, it is rational to assign a higher probability to the conjunction of suitably chosen propositions than to one of the conjuncts. By pointing out the similarities between Tversky and Kahneman’s experiment and our example, we argue that the participants in the experiment may assign probabilities to the propositions in question in such a way that it is also rational for them to give the conjunction a higher probability than one of the conjuncts.


Conjunction fallacy Linda problem Psychology of reasoning Bayesian epistemology 


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Copyright information

© Springer Science+Business Media B.V. 2009

Authors and Affiliations

  1. 1.Tilburg Center for Logic and Philosophy of ScienceTilburg UniversityTilburgThe Netherlands

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