This paper concerns the relationship between epistemology and radically extended cognition. Radically extended cognition (REC) – as advanced by Andy Clark and David Chalmers – is cognition that is partly located outside the biological boundaries of the cognizing subject. Epistemologists have begun to wonder whether REC has any consequences for theories of knowledge. For instance, while Duncan Pritchard suggests that REC might have implications for which virtue epistemology is acceptable, J. Adam Carter wonders whether REC threatens anti-luck epistemology. In this (...) paper, I argue that the possibility of REC has no systematic consequences for theorizing in epistemology. I suggest an alternative relationship between the two: epistemology can play a role in diagnosing cases of REC. Thus, by establishing that entities partially located outside biological boundaries don't play certain epistemic roles, one can establish that they don't play the related cognitive roles either. I conclude the paper by illustrating this last point. (shrink)