What are the consequences of evolutionary theory for the epistemic standing of our beliefs? Evolutionary considerations can be used to either justify or debunk a variety of beliefs. This paper argues that evolutionary approaches to human cognition must at least allow for approximately reliable cognitive capacities. Approaches that portray human cognition as so deeply biased and deficient that no knowledge is possible are internally incoherent and self-defeating. As evolutionary theory offers the current best hope for a naturalistic epistemology, evolutionary approaches to epistemic justification seem to be committed to the view that our sensory systems and belief-formation processes are at least approximately accurate. However, for that reason they are vulnerable to the charge of circularity, and their success seems to be limited to commonsense beliefs. This paper offers an extension of evolutionary arguments by considering the use of external media in human cognitive processes: we suggest that the way humans supplement their evolved cognitive capacities with external tools may provide an effective way to increase the reliability of their beliefs and to counter evolved cognitive biases.