The philosophical significance of attitudinal autonomy-viz., the autonomy of attitudes such as beliefs-is widely discussed in the literature on moral responsibility and free will. Within this literature, a key debate centres around the following question: is the kind of attitudinal autonomy that's relevant to moral responsibility at a given time determined entirely by a subject's present mental structure at that time? Internalists say 'yes', externalists say 'no'. In this essay, I motivate a kind of distinctly epistemic attitudinal autonomy, attitudinal autonomy that is relevant to knowledge. I argue that regardless of whether we are externalists or internalists about the kind of attitudinal autonomy that is relevant for moral responsibility, we should be externalists about the kind of autonomy that a belief must have to qualify as knowledge.