Philosophers have almost always relegated the topic of revision to the sidelines of their discipline, if they have thought about it at all. This book contends that acts of revision are central and indispensable to the project of philosophizing and that philosophy should be construed essentially as a practice of rereading and rewriting. The book focuses chiefly on Heidegger s highly influential interpretation of Nietzsche, conducted in lectures during the 1930s and 1940s and published in 1961. The author closely analyzes the rhetorical means by which Heidegger repositions Nietzsche s thinking within a broad history of metaphysics, even as Heidegger positions his own reinterpretation as that history s more proper reading. The author argues that Heidegger s revisionist project recasts the philosophical text as paralipsis, a special kind of ironic statement that when properly received by the philosophical rereader, expresses what the text did not and could not say. The study of such paraliptical revisionism within the philosophical canon offers a new way of understanding the basic historicity of the philosophical text, a text that is critically indistinguishable from its own future history of interpretations. Philosophy itself is revision, a deeply historicist rereading practice, a continuous reappropriation of its own improper textual past.