The Structure of Idealization in Biological Theories: The Case of the Wright-Fisher Model



In this paper we present a new framework of idealization in biology. We characterize idealizations as a network of counterfactual and hypothetical conditionals that can exhibit different “degrees of contingency”. We use this idea to say that, in departing more or less from the actual world, idealizations can serve numerous epistemic, methodological or heuristic purposes within scientific research. We defend that, in part, this structure explains why idealizations, despite being deformations of reality, are so successful in scientific practice. For illustrative purposes, we provide an example from population genetics, the Wright-Fisher Model.


Idealization Epistemic virtues Scientific models Modeling in biology Population genetics Wright-Fisher Model 



This paper has received financial support from the Spanish Ministry of Science and Innovation (Research Project Ref.: FFI2009-08828/FISO). A postdoctoral fellowship was awarded to Alfonso Arroyo Santos by the CONACyT (“Programa de Estancias posdoctorales vinculadas al fortalecimiento de la calidad del posgrado nacional” 2010). Previous versions of this article were presented at different conferences, including the PSA Biennial Meeting held on November 6–8, 2008 in Pittsburgh. The authors would like to thank the audiences on those occasions, and specially Mark E. Olson and two anonymous referees of this journal for their helpful comments.


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© Springer Science+Business Media B.V. 2012

Authors and Affiliations

  1. 1.Department of Logic and Moral PhilosophyUniversity of Santiago de CompostelaSantiago de CompostelaSpain
  2. 2.Facultad de Filosofía y Letras, Posgrado en Filosofía de la CienciaUNAMMexico CityMexico

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