Abstract

In very recent Leibniz commentary, there has been a movement among some commentators toward the view that Leibniz was not an unwavering monadological immaterialist, committed to the substantiality only of absolutely simple, immaterial nodes of perception and appetite. It has been conceded that Leibniz was also partially sympathetic to an ontology that would concede full substantiality to composite entities. Most commentators who have been willing to concede as much have confined this alternative metaphysics to Leibniz's middle period, roughly 1676--1694. These commentators, moreover, have remained fairly silent as to the reasons why Leibniz might wish to consider an ontology at such odds with his well-known immaterialism. In this dissertation, I contribute to the discussion of Leibniz's composite-substance metaphysics in three ways. First of all, I am going to argue that we should see the composite-substance metaphysics as an alternative Leibniz sustained until the very end of his career. Second of all, I provide an account of Leibniz's motivation for sustaining this alternative metaphysics, arguing that the composite-substance metaphysics is first and foremost the result of Leibniz's effort to provide a philosophical interpretation of the recent discovery of the apparent ubiquity of microscopic life. Finally, I vindicate a number of 18th-century, microorganic and physicalistic interpretations of Leibniz's theory of monads, particularly those of the Francophone natural scientists, against the view among 20th-century commentators that Leibniz was grossly misinterpreted in the decades following his death in 1716. I show that 18th-century, thinkers didn't so much misinterpret Leibniz, as they did emphasize one, currently very unfamiliar, tendency in Leibniz's thought on the nature of substance