In Delusions and Beliefs (2019), Kengo Miyazono proposes an extended and convincing argument for the thesis that delusions are malfunctional beliefs. One of the key assumptions for this argument is that belief is a biological notion, and that the function of beliefs is a product of evolution. I challenge the thesis that evolutionary accounts can furnish an epistemologically satisfying account of beliefs because evolutionary success does not necessarily track epistemic success. Consequently, also delusions as beliefs cannot be explained in a satisfactory manner by looking at beliefs’ evolutionary function. How can we then salvage the notion of delusions as epistemologically relevant malfunctioning beliefs? I propose that knowledge-first epistemology gives us a way out. Knowledge-first accounts argue that knowledge is more primitive than belief. That is, knowledge is not a kind of successful beliefs (true, justified, etc.); instead, beliefs are failed attempts at knowledge. Being a belief derives from the norms of knowledge. Explaining the epistemology of beliefs through the primitive norms of knowledge, we can also explain why delusions are malfunctional beliefs: The cognitive and psychological defects that produce delusions block the beliefs from becoming knowledge. Consequently, delusions are attempts at knowledge that have failed particularly badly.