Matter & Space, Plato & Aristotle: The Receptacle of Plato’s Timaeus as Aristotelian Prime Matter

Abstract

In the Timaeus, Plato presents his natural philosophy of the origins of the cosmos, space, and the four elements. In the ‘Receptacle passage’ of Timaeus 47e-53c, the eponymous speaker Timaeus affirms that the three underlying components of the cosmos are intelligible Platonic Being, sensible Becoming, and the Receptacle and that the Receptacle is space. In Timaeus 53c-57d, he proceeds to present a geometric construction of the four elements of air, fire, water, and earth from two basic triangles into four corresponding regular Platonic solids that constitute a corpuscle of each element. Based upon these passages, Aristotle interprets the Timaeus as presenting Plato’s theory of matter, where Platonic matter is space itself and matter is composed of geometric planes. In this thesis, I explore the function and role of the Receptacle and its relationship with the geometric construction of the four elements. I argue that the Timaeus presents an account of Platonic compounds (or elemental bodies), which are constituted by the Receptacle (as an underlying Platonic matter or substratum), Platonic Becoming, and images of the intelligible Platonic Being. I show that Aristotle’s characterization is true, Platonic matter is space, which is the Receptacle. My major finding is that the Platonic account of elemental bodies prefigures Aristotelian hylomorphism. The Receptacle is an Aristotelian prime matter and the images of Platonic Being are Aristotelian forms. However, since Plato and Aristotle have starkly diverging metaphysical accounts of change and Becoming, Platonic Becoming lacks a clear counterpart in Aristotelian natural philosophy.