ABSTRACT
The single most important Presocratic thesis regarding the material composition of natural beings is probably that there are bodies, called “elements,” from which all natural beings are constituted and into which they all dissolve. Stoic physics firmly belongs to this tradition and the aim of the present chapter is to present in detail the elemental theory of the Stoics. A detailed discussion is offered of the main source for this theory—Arius Dydimus fr. 21—and of the main current interpretation of this text, John Cooper’s “Chrysippus of physical elements” (Cooper 2009). The discussion is centered on the question of why the Stoics did not regard the two principles of their physics, namely, god and matter, as elements and restricted the use of the term “element” to the four traditional elements, i.e. ordinary fire, air, water and earth.
