IntroductionI. The Earlier Dogmatic Philosophies
The writings of Sextus contain not only an exposition of Scepticism but also a critique of the doctrines of “the Dogmatists.” The main task of the Sceptic is, in fact, to expose the folly of every form of positive doctrine; and consequently the bulk of these works of Sextus is controversial. Scattered through his pages there are references to almost every known name in the history of ancient Greek thought, and without some previous acquaintance with the main outlines of that history it is hardly possible to appreciate the points or estimate the value of his arguments. Accordingly I give here, for the convenience of the reader, a short summary of the history of Greek philosophy.
1. The Ionian Physicists.—Of the School of Miletus the founder was Thales (circa 600 b.c.). He declared that the fundamental substance of which the world was made is water. His successor, Anaximander (circa 570 b.c.), described that substance as “the boundless” (τὸ ἄπειρον), since out of it were formed “countless” (ἄπειροι) worlds. He regarded this primitive stuff as being in itself indeterminate, or of no one definite quality, and evolving into the forms of earth, fire, etc., by a process of “separation” of hot from cold, moist from dry, etc. Also he called his primal substance “divine.” Anaximenes (circa 540 b.c.), like Thales, took one definite element as his primary