Cognitive abilities have been invoked to do much work in externalist epistemology. An ability condition (sometimes in conjunction with a separate, anti-luck condition) is seen to be key in satisfying direction-of-fit and modal stability intuitions which attach to the accrual of positive epistemic status to doxastic attitudes. While the notion of ability has been given some extensive treatment in the literature (especially John Greco, Alan Millar and Ernest Sosa), the implications for these abilities being particularly cognitive ones has been given less attention. To rectify this oversight, I examine the debate over the nature of cognition from philosophy of cognitive science, paying particular attention to the debate between defenders of internalist theories (Fred Adams, Kenneth Aizawa and Rob Rupert) and externalist theories (so-called “extended mind” positions). Armed with substantive accounts of cognition, I argue that the epistemological externalist’s obligation to repudiate epistemological internalism forces her to adopt some sort of externalist account of cognition.