 But why would Leibniz use a term like “composite substance” in the Principes de la Nature et de la Grace if it did not accurately reflect his considered position? Here is one possible answer. In presenting his theory of simple substances Leibniz was concerned to avoid a fundamental misunderstanding. The misunderstanding is that if the only true substances are unextended simple substances, then bodies must be mere illusions. Leibniz does not think that bodies are mere illusions. His view of bodies (from the perspective of the theory of monads) is, roughly, that they are “real but not fully real”. To adequately grasp Leibniz’s view one must understand that his ontology countenances different levels or degrees of reality. Simplifying things considerably, these degrees range from the ideal (the least real) to the phenomenal (mid-grades of reality) to the level of monads (the most real). Bodies fall within the purview of the phenomenal: they are more real than entities that are purely ideal (e.g., space) but less real than simple substances. Bodies are accorded an enhanced degree of reality (in comparison to merely ideal entities) because they are well founded on the reality of monads. The precise nature of this “well founding”—and of Leibniz’s ontological scheme more generally—is a complicated and controversial matter. The nuanced framework (however one might fill in the details) does not lend itself to a straightforward and intuitive presentation in several paragraphs of text (see Whipple 2020 for a more detailed account).