Chapter V.

After these arose also other natural philosophers, whose opinions we have not deemed it necessary to declare, (inasmuch as) they present no diversity to those already specified. Since, however, upon the whole, a not inconsiderable school has sprung (from thence), and many natural philosophers subsequently have arisen from them, each advancing different accounts of the nature of the universe, it seems also to us advisable, that, explaining the philosophy that has come down by succession from Pythagoras, we should recur to the opinions entertained by those living after the time of Thales, and that, furnishing a narrative of these, we should approach the consideration of the ethical and logical philosophy which Socrates and Aristotle originated, the former ethical, and the latter logical. ¹