Against the tendency to regard Deleuze as a materialist and a naturalistic thinker, I argue that his core philosophical writings involve commitments that are incompatible with contemporary scientific naturalism. He defends different versions of a distinction between philosophy and natural science that is inconsistent with methodological naturalism and with the scientific image of the world as a single causally interconnected system. He defends the existence of a virtual realm of entities that is irreconcilable with ontological naturalism. The difficulty of reconciling (...) Deleuze’s philosophy with ontological naturalism is especially apparent in his recurrent conception of pure events that are irreducible to their incarnation in bodies and states of affairs. In the last section of this essay, I canvass some of the ways in which Deleuze’s thought might be reconciled with a more liberal, pluralist and ethical naturalism that he identified in an early essay on Lucretius. (shrink)