This groundbreaking book engages with the relationship between ontology, metaphysics, and epistemology in Heidegger and Deleuze. Showing that the latter are rooted in their respective ontologies not only provides a clear, detailed, and holistic outline of all three, but also reveals that Heidegger and Deleuze are highly critical of thinking that associates being with identity. While they both seek to overcome this association by affirming being as becoming, they differ in terms of what this becoming entails with Deleuze's onto-genetic account of being's rhizomic-becoming going beyond Heidegger's temporal account. However, while Deleuze attempts to think as and from difference, the relationship between identity and difference is explored to offer a tri-partite account of identity that shows that, despite his claims to the contrary, Deleuze's ontological categories continue to depend on a form of the identity he aims to overcome.