Descartes's teleomechanics in medical context: Approaches to Integrating Mechanics and Teleology in Hieronymus Fabricius ab Aquapendente, William Harvey, and Rene Descartes

In this dissertation, I examine the relation between mechanism and teleology in Descartes's physiology, placing his views in a wider medical and anatomical context. I show that in this context we find distinctively Galeno-Aristotelian approaches to integrating mechanics and teleology in the work of anatomists Hieronymus Fabricius ab Aquapendente and his more famous student, William Harvey. I provide an interpretation of teleology and mechanism in Descartes by exploring the historical and conceptual relationships between his approach and those exhibited by these anatomists.;First, I show that Fabricius and Harvey articulate creative, teleological, non-reductive approaches to mechanizing the animal precisely by developing Aristotelian and Galenic resources. They propose that mathematical mechanics, understood as an Aristotelian subordinate science, should be employed to articulate the way the functions of the locomotive organs explain (as final causes) certain features of their anatomy, rendering them hypothetically necessary. They articulate these explanations using the Galenic concepts actio and usus.;Employing the resources developed in my analysis of Fabricius and Harvey, I then provide a new interpretation of the relation of mechanism and teleology in Descartes and clarify its significance. Although he explicitly rejects final causes in natural philosophy, Descartes still appeals in physiology to apparently teleological concepts like functio and usus. By focusing on the medical context of these concepts, I show that Descartes intends to and primarily does employ these concepts in mechanical explanations. Descartes' explanations are meant to replace the metaphysically more extravagant but still material-efficient (not final-causal) explanations present in the medical tradition. I then argue that Descartes at times does in fact employ final-causal explanations similar to those in Fabricius's and Harvey's work. However, Descartes is hard-pressed to ground these explanations while still rejecting both divine purposes and non-mechanical principles in natural philosophy.