Abstract
This paper critiques Alvin Plantinga's evolutionary argument against naturalism. Plantinga argues that, since unplanned evolution is not likely to produce trustworthy cognitive faculties, evolutionary naturalists cannot rationally believe anything--including naturalism itself. This paper contends that this argument rests on a crucial but faulty inference from the premise that the probability that our cognitive faculties are reliable given unplanned evolution is low or inscrutable. The conclusion that evolutionary naturalists cannot rationally believe in unplanned evolution does not follow from this "probability thesis." If the thesis were amended to claim that the probability of reliable cognitive faculties given unplanned evolution is low (as opposed to "low or inscrutable"), then it would follow that naturalists cannot trust their cognitive faculties; but this amended thesis is demonstrably false, and thus Plantinga's evolutionary argument against naturalism fails.