In NDPR, Kevin Hart reviews Jean-Luc Marion's Negative Certainties.
Early phenomenology starts as a criticism of epistemology, as practiced in Husserl's day; it is directed against psychologism, and also against empiricism with its view that ideas and perceptions are mere representations. It seeks to secure firm knowledge by way of leading any transcendent thing to the immanence of consciousness cleansed of psychological or empirical adhesions. This process of leading back is what Husserl calls "reduction," and its theory was to concern him (and distract him) for decades. Suffice it to say that reduction does not lead one to a separate internal state, as Eugen Fink urges us to believe, but only to givenness [Gegebenheit], and that to a greater or lesser degree. Did Husserl's reduction truly lead to givenness, however? Heidegger doubted it, thinking that Husserl remained trammeled in a theoretical distinction between subject and object, and maintained that the genuine reduction was from beings to being; and, in his turn, Marion has argued that a "third reduction" is needed, one that slips past Husserl's metaphysics of the subject and even Heidegger's meditations on Sein and reaches givenness itself.