Book 1
2
THE followers of Aristotle and Plato conclude that the elements are discriminated from a principle. Thales the Milesian supposeth that a principle and the elements are one and the same thing, but it is evident that they vastly differ one from another. For the elements are things compounded; but we do pronounce that principles admit not of a composition, nor are the effects of any other being. Those which we call elements are earth, water, air, and fire. But we term those principles which have nothing precedent to them out of which they are produced; for otherwise not these themselves, but rather those things whereof they are produced, would be the principles. Now there are some things which have a pre-existence to earth and water, from which they are begotten; to wit, matter, which is without form or shape; then form, which we call ἐντελέχεια (actuality); and lastly, privation. Thales therefore is very peccant, by affirming that water is both an element and a principle.
Chapter III. OF PRINCIPLES, AND WHAT THEY ARE.
