Barbara Michaela Sattler

University of St. Andrews

Barbara Michaela Sattler is a senior lecturer at University of St. Andrews, Department of Philosophy. Previously, she was an assistant professor at Yale University (2007-2013). She has published The Concept of Motion in Ancient Greek Thought: Foundations in Logic, Method, and Mathematics (CUP, 2020), edited One Book, the Whole Universe: Plato's Timaeus Today (Parmenides, 2010), co-edited Ancient Ethics and the Natural World (CUP, 2021) and published numerous articles on ancient metaphysics and natural philosophy in OSAP, Journal of the History of Philosophy, Ancient Philosophy and elsewhere.

Abstract

Proportion and friendship in Plato’s Timaeus

Plato employs mathematical structures in the Timaeus in order to demonstrate that the phenomenal world displays a substantial degree of intelligibility. I begin this paper by discussing one central problem of this mathematisation, namely that arithmetic and geometry seem to be tied to different ontological realms in the Timaeus: while arithmetic is closely tied to the world soul and time, geometry is employed for the material bodies in the space-like receptacle. In a second step I investigate Plato’s usage of proportion theory as an attempt to unify arithmetical and geometrical structures and as a bond that can bestow unity and thus friendship among the parts.