Plutarch, Aquane an ignis sit utilior
Harold Cherniss and William C. Helmbold, Ed.

What could anyone find to say on the other side from this point on ? This, that God, the master workman, had as material four elements from which to construct the universe. Among these, again, there is a simple mutual distinction, namely, that earth and water are a foundation at the bottom of the universe, being, like raw material, the substance of which things are constructed and moulded, having just so much form and organization, and indeed of capacity for growth and procreation, as is imparted to them by the other elements, air and fire, which are makers and artisans and rouse them, lying lifeless as they were until then, to the act of creation. Between these two, again, fire and air, there is the distinction that fire assumes the rule and leadership. This is clear by induction¹: earth without warmth [p. 301] is barren and unfruitful, but fire, when it takes possession and inflames, causes it to swell to the point of generation ; and it is impossible to find anyother reason why rocks and the bare bones of mountains are barren except that they have either no part at all, or very little share, in fire.