Early in Book V of his Tusculan Disputations Cicero gave what has become a classic expression of the Socratic turn of philosophy.
But from the earliest philosophy to the time of Socrates, who sat under Archelaus, a disciple of Anaxagoras, motion and number were explored as well as the origin and destiny of all things; those philosophers zealously inquired after the sizes of the stars, the distances between them, their paths and all heavenly phenomena. Socrates was the first to call philosophy down from the heavens, to set it in the cities and even to bring it into the household; he compelled it to inquire into life and character and issues of good and evil [de vita et moribus rebusque bonis et malis] (Tusc. 5. 10-11).