According to proponents of radically extended cognition, some cognition is located outside the boundaries of biological organisms. In this paper, I offer a new argument for a modest version of this view according to which some cognitive processes are radically extended. I do so by showing that features of a subject's environment—in particular, the pen and paper that a subject uses to solve complex mathematical problems—can have epistemic roles that are indicative of cognitive roles. I end the paper by discussing (...) how epistemology might play a significant role in diagnosing alleged cases of radically extended cognition. (shrink)