The Principles of Natural Things—Two or Three?

Abstract

This chapter examines part 2 of Physics I 7, in which Aristotle connects the concepts of what underlies and of the contraries with the question of what the principles of natural things are. He articulates the concept of the contraries involved in any given change in terms of the distinction between form and privation. He privileges form over privation, treating only form and matter as indispensable principles of natural substances. Furthermore, he focuses on the principles of the being and coming-to-be of substances, at the expense of the non-substantial forms of change such as alteration and locomotion. He also introduces the idea that form is not only a principle of natural substances once they have come to be, but also a principle from which they come to be. Aristotle employs these new thoughts in stating his own view of what the principles of natural things are: form, privation, and the substratum that underlies them.