In what follows I examine Diderot’s chemically influenced vital materialism. Once condemned as “mechanistic,” materialism has had something of a renaissance in recent decades as scholars have rediscovered a tradition of “vital materialism” which they have opposed to older, cruder forms of the idea, e.g. materialisms full of life, affect, chimiatry, and transformation. Sometimes these rediscoveries have attached themselves to a figure of the past, like Margaret Cavendish’s metaphysics of active matter, or to a construct of the still-emerging future, like Karen Barad’s quantum physics-nourished “agential realism” present in all of matter. Another question concerns the extent to which these revivals of “vital” or “active-matter” materialism should be traced back to older Renaissance naturalisms. In what follows, I return to Diderot and the question of his “vital materialism.” Diderot draws both on older traditions, approvingly citing Van Helmont and gesturing towards a new chemistry of living matter and also speaks the language of scientific revolution, writing that “We are on the verge of a great revolution in the sciences.” In earlier work I sought to connect this language of revolution in the sciences to the emergence of biology as a science. Here I focus on his chemically charged materialism.