, Volume 193, Issue 9, pp 2987–3001 | Cite as

In defense of proper functionalism: cognitive science takes on Swampman

  • Kenny Boyce
  • Andrew MoonEmail author


According to proper functionalist theories of warrant, a belief is warranted only if it is formed by cognitive faculties that are properly functioning according to a good, truth-aimed design plan, one that is often thought to be specified either by intentional design or by natural selection. A formidable challenge to proper functionalist theories is the Swampman objection, according to which there are scenarios involving creatures who have warranted beliefs but whose cognitive faculties are not properly functioning, or are poorly designed, or are not aimed at truth. In this paper, we draw lessons from cognitive science in order to develop a novel argument for the conclusion that the Swampman objection fails against proper functionalist theories of warrant. Our argument not only shows that the underlying, central intuition motivating Swampman-like scenarios is false but also motivates proper function as a necessary condition for warrant, thereby lending support to the claim that any theory of knowledge that lacks a proper function requirement is false.


Swampman Warrant Knowledge Proper functionalism 



We are grateful to Sarah Boyce, Matthew Lee, Josh May, Matthew McGrath, Alvin Plantinga, Ted Poston, and Ernie Sosa for helpful correspondence and conversation concerning these matters. We are also thankful to the audience at the 2015 MidSouth Philosophy conference, including Matthew Frise, Derek Jones, Kevin McCain, Alex Radulescu, Josh Smart, and especially our commentator Nick Byrd.


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Copyright information

© Springer Science+Business Media Dordrecht 2015

Authors and Affiliations

  1. 1.University of MissouriColumbiaUSA
  2. 2.Rutgers UniversityNew BrunswickUSA

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