Leibniz, Spinoza and the Anti-Cartesian Reaction
This chapter looks in detail at the three main engagements with Leibniz in the main text of Deleuze’s Expressionism in Philosophy: Spinoza. The first concerns the role of real definitions and proofs of possibility in arguments for the existence of God. The second concerns the theory of adequation in a logic of ideas. The third concerns mechanism, force and essence in a theory of bodies. The chapter argues that these engagements all share the same form. First, Deleuze locates a similarity between Leibniz and Spinoza in their criticism of a particular Cartesian doctrine. Second, he grounds this criticism in a shared concern for the lack of a sufficient reason operating in Descartes’s philosophy. Third, he nominates expression as the concept best suited to address this lack and fulfil the requirements of sufficient reason. Finally, he shows that the way expression functions in Spinoza’s philosophy is each time superior to Leibniz’s own use of the concept. Despite the priority given to Spinoza in this text, it nevertheless contains our first introduction to various key Leibnizian concepts which will become increasingly important in Deleuze’s later philosophy.