Heidegger's deconstruction of the history of Western metaphysics has been a major influence behind poststructural critiques of modernity as well as more apologetic attempts to maintain a dialogue with historical sources, such as Gadamer's philosophical hermeneutics. This bifurcation has intensified the ambiguity of Heidegger's project: was it an attempt to relinquish philosophical ties to the past or a call for a fundamental reinterpretation of them? In this article I argue the latter, focusing my analysis on Heidegger's notions of appropriation and historicity. On the one hand, appropriation is the hermeneutical event by which ontology is reinfused into a reading of historical sources. On the other hand, historicity is the self-reflexive historical involvement by which we become aware of what contemporary, philosophical conditions necessitate this reengagement. In the end, Heidegger's critique of metaphysics arises from this self-reflexivity. It deconstructs the prevailing misunderstandings of philosophical sources in order to allow for reinterpretation at a revivified ontological level constantly in view of the question of being.