Truth-Reliability and the Evolution of Human Cognitive Faculties

Abstract

Many philosophers have claimed that evolutionary theory provides good reason to believe that human cognitive faculties are reliable. Specifically, they claim that reliable cognitive faculties enjoy a selective advantage over unreliable cognitive faculties. Thus, it is concluded that natural selection favors cognitive faculties that are capable of fulfilling the epistemic goal of having mostly true beliefs. In this paper, I argue that the fact that human cognitive faculties have an evolutionary origin provides no reason to accept the claim that they are reliable with respect to generating true beliefs. While evolution might warrant the claim that human cognitive faculties are adaptive (or fitness-enhancing), the claim that human cognitive faculties reliably generate true beliefs is not supported by an appeal to evolution. I begin by constructing an argument linking natural selection with reliability. I argue, however, that such an argument fails because itexploitsan ambiguitybetween twodistinctnotionsofreliability:fitness-reliabilityand truth-reliability.While it is plausibleto think that our cognitive faculties are fitness-reliable, our epistemic goals require them to be truth-reliable. After discussing reasons for doubting whether true beliefs are more adaptive than false beliefs, I conclude that natural selection provides no reason to suppose that human cognitive faculties are truth-reliable.