Toland, Leibniz, and Active Matter

Early in the eighteenth century Leibniz had several interactions with John Toland. These included discussions of materialism, which culminated with the consideration of Toland's 1704 Letters to Serena. There Toland argued that matter is necessarily active. This chapter argues for two main theses about this exchange and its consequences for our wider understanding. First, despite many claims that Toland was at the time of Letters to Serena a Spinozist, we can make better sense of him as a sort of Hobbesian materialist. The second main point concerns reasons for materialism, and in particular a story Locke tells in the Essay about materialists' motives and their use of conceivability arguments. Toland did use a conceivability argument, as indeed did Hobbes. But these were not the crude conceivability arguments that Locke suggests motivate materialists. We might tell a Lockean story about reasons for early modern materialism, but not Locke's story.