On an ‘internalist’ picture, knowledge isn’t necessary for understanding the nature of perception and perceptual experience. This contrasts with the ‘knowledge first’ picture, according to which it’s essential to the nature of successful perceiving as a mental state that it’s a way of knowing. It’s often thought that naturalistic theorizing about the mind should adopt the internalist picture. However, I argue that a powerful, recently prominent framework for scientific study of the mind, ‘predictive processing,’ instead supports the knowledge first picture. (...) Under predictive processing, it’s intrinsic to successful perceiving that it’s a state with the kind of modal robustness that’s distinctive of knowledge, which gives us reason to think of successful perceiving along knowledge first lines. Furthermore, I argue that the predictive processing framework encourages us to conceptualize experiences which don’t amount to knowledge along knowledge first lines, as states which by their nature fall short of knowledge. (shrink)