This review-essay examines Martin Jay’s The Eclipse of Reason: On Late Critical Theory with a view toward understanding the stakes of its interpretative approach to intellectual history. I show how Jay's book aims to provide much more than a mere history of reason (although it does this admirably), for it seeks to legitimate and resuscitate an idea of reason in the face of more than one hundred years of anti-rationalist thought. I contend that Jay offers Habermas’s intersubjective rationality (“late Critical Theory”) as both an alternative to, but also in some sense a continuation of, the dominant forms of subjectivist and objectivist rationality Jay documents in his book. According to the logic of Jay’s account, then, Habermas represents in some sense the fulfillment of the history of Western rationality. My only critique of an otherwise excellent and fascinating study is that Jay’s Frankfurt School-centric narrative effectively inhibits a larger discussion of Habermas’s relevance to recent and current debates about the direction of philosophy. An elaboration specifically of the post-structuralist critique of reason would have greatly enhanced our understanding of the place of "late Critical Theory" in the intellectual landscape of our time.