| dc.description.abstract | This thesis investigates Aristotle's criticism and consequent reformulation of the
Platonic method for formulating definitions called the Method of Division. For both
Plato and Aristotle, the object of division is a natural kind, which consists in a class
whose members stand in a homologous relationship to a single form. I argue that
Aristotle's criticisms of the Method of Division fall under two categories: logical
objections and ontological objections. The logical objections focus on division as a
method for demonstrating definitions, a method that Aristotle wants to distinguish
from his syllogistic logic, the centerpiece of his theory of scientific demonstration. The
ontological objections focus on the question of whether the sort of account generated
by division is sufficient to constitute a definition of its object. Aristotle's revised
Method of Division is supposed to avoid the problems he raises by constructing
definitions that satisfy the principles motivating his ontological objections through
a logical process devised to make the resulting account a "necessary" consequence of
the initial assumptions of the division.
I argue that Aristotle?s ontological objections to the Method of Division reflect a
deeper disparity between the Platonic and the Aristotelian notion of a form and natural
kind. Underpinning Aristotle's notion of a natural kind is an ontology of discrete
substances. Because the unity of substance is paramount in this ontology, Aristotle argues that a definition, which is supposed to give an account of the essence of a substance,
must account for the unity of its object by itself possessing a non-accidental
unity. Yet, on a Platonic ontology, a definition by division invokes a plurality of
independent Forms whose conjunction does not constitute a unity. On the basis of
this consideration, Aristotle argues that an ontology of abstract Forms cannot account
for the unity of an individual substance. To this extent, I conclude, Aristotle's
methodological objections to the Platonic Method of Division are a component of
his broader criticisms of Platonic metaphysics. | en |
