  What makes an experience conscious is a certain awareness one has of the experience while living through or performing it. This form of inner awareness has been a topic of considerable debate, centuries after the issue arose with Locke’s notion of self-consciousness on the heels of Descartes’ sense of consciousness (conscience, co-knowledge). Does this awareness-of-experience consist in a kind of inner observation of the experience, as if one were doing two things at once? (Brentano argued no.) Is it a higher-order perception of one’s mind’s operation, or is it a higher-order thought about one’s mental activity? (Recent theorists have proposed both.) Or is it a different form of inherent structure? (Sartre took this line, drawing on Brentano and Husserl.) These issues are beyond the scope of this article, but notice that these results of phenomenological analysis shape the characterization of the domain of study and the methodology appropriate to the domain. For awareness-of-experience is a defining trait of conscious experience, the trait that gives experience a first-person, lived character. It is that lived character of experience that allows a first-person perspective on the object of study, namely, experience, and that perspective is characteristic of the methodology of phenomenology.