, Volume 195, Issue 2, pp 491–510 | Cite as

Rational analysis, intractability, and the prospects of ‘as if’-explanations

  • Iris van RooijEmail author
  • Cory D. Wright
  • Johan Kwisthout
  • Todd Wareham


The plausibility of so-called ‘rational explanations’ in cognitive science is often contested on the grounds of computational intractability. Some have argued that intractability is a pseudoproblem, however, because cognizers do not actually perform the rational calculations posited by rational models; rather, they only behave as if they do. Whether or not the problem of intractability is dissolved by this gambit critically depends, inter alia, on the semantics of the ‘as if’ connective. First, this paper examines the five most sensible explications in the literature, and concludes that none of them actually circumvents the problem. Hence, rational ‘as if’ explanations must obey the minimal computational constraint of tractability. Second, this paper describes how rational explanations could satisfy the tractability constraint. Our approach suggests a computationally unproblematic interpretation of ‘as if’ that is compatible with the original conception of rational analysis.


Psychological explanation Rational analysis Computational-level theory Intractability NP-hard Approximation 


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Copyright information

© Springer Science+Business Media Dordrecht 2014

Authors and Affiliations

  • Iris van Rooij
    • 1
    Email author
  • Cory D. Wright
    • 2
  • Johan Kwisthout
    • 1
  • Todd Wareham
    • 3
  1. 1.Donders Institute for Brain, Cognition, and BehaviourRadboud Universiteit NijmegenNijmegenThe Netherlands
  2. 2.Department of PhilosophyCalifornia State University Long BeachLong BeachUSA
  3. 3.Department of Computer ScienceMemorial University of NewfoundlandSt. John’sCanada

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