Abstract

This paper offers a commonsense response to Alvin Plantinga’s evolutionary argument against naturalism. The first stage of that argument concludes that the probability that our cognitive faculties are reliable (R) is low or inscrutable given the claims that naturalism is true (N) and that our cognitive faculties came into existence by way of the mechanisms of evolution (E)—i.e., that P(R/N&E) is low or inscrutable. The second stage claims that the fact that P(R/N&E) is low or inscrutable constitutes a defeater for belief in R, for anyone who endorses N&E. For the purposes of this paper, I will grant to Plantinga the conclusion of the first stage of his argument—that P(R/N&E) is low or inscrutable when specified to us. My contention is simply that, given what we can know via commonsense, this does not necessarily constitute a defeater for R for the supporter of N&E.