This thesis motivates a novel account of desire as the best explanation of an intuitive datum. The intuitive datum is that often when an agent desires P she will immediately, outright know that she has a reason to bring P about. Existing explanations of the intuitive datum cannot simultaneously satisfy two desiderata. We want to explain how desires enable outright knowledge of reasons and also explain the fallibility of desires. Existing views satisfy the first desideratum at the expense of the (...) second, or vice versa. I propose an epistemological disjunctivist account of desire that satisfies both. On this view, a desire for P represents the value of P in a manner analogous to perception. Desires come in two distinct epistemic kinds: an awareness of value or an illusion of value. An awareness of value enables outright knowledge of reasons and allows the agent to tell by reflection that she has such knowledge. An illusion of value merely seems to provide grounds for knowledge, which explains the fallibility of desires. The proposed account is a strong candidate for the truth because it best explains central features of our practical agency. (shrink)