This dissertation focuses on an introspective phenomenon that I call primitive introspection. Primitive introspection is a non-classificatory kind of phenomenal-state introspection: it is a kind of phenomenal-state introspection that does not involve recognizing the introspected phenomenal state as an instance of any experience type. I defend three main claims about primitive introspection. First, it exists: there is a mental phenomenon that has the features I attribute to primitive introspection and such a phenomenon is a fullfledged introspective process. Second, its nature is best accounted for by a version of the acquaintance theory—what I call the integration account. Third, it has a distinct epistemic value: it provides the subject wi...