Stoic unformed substance and old academic ontology - UCL Discovery

Abstract:
This thesis examines the influences on the Stoics‟ development of their material
principle. The thesis argues that the reasons for the Stoics‟ conceiving of a material
principle as they did actually have their origins in metaphysical speculation rather
than physics.
While the natural philosophy of the Ionians, as interpreted by Aristotle and his
followers, no doubt furnished the intellectual background for a persisting material
substrate of all sensible change, it is in fact the concerns of Plato and his early
followers with the non-sensible that exert the strongest influence on the Stoics.
The thesis examines the concepts of space and matter in the Timaeus ultimately
rejecting this work of physics as central to the development of Stoic thought on
matter. Rather it is the metaphysical doctrines of Plato and his successors, and the
use they make of an incorporeal matter, that exerted the greatest influence on the
Stoics and their material principle. The interpretation of Platonic metaphysics argued
for in the thesis, based on the Unwritten Doctrines and the Old Academy‟s teachings,
challenges the majority opinion of the English speaking community; and as a result
offers a novel understanding of the relationship of Stoicism to Platonic metaphysics.
The thesis concludes that it is likely that the early Stoics developed their doctrine of
a material substrate in the particular way they did because of the tendency in the
Old Academy to simplify the doctrines of Plato. This simplifying tendency comes to a
head in the early Stoics with the ultimate reduction of the Old Academic system of
hypostases, making use of active and passive principles at various levels of reality,
finally ending in one level of reality and a simple two principle system.
3 Stoic Unformed Substance and Old Academic Ontology