Institutio Oratoria

However, to say nothing of Homer, in whom we may find either the perfect achievements, or at any rate clear signs of the knowledge of every art,

and to pass by Hippias of Elis, who not merely boasted his knowledge of the liberal arts, but wore a robe, a ring and shoes, all of which he had made with his own hands, and had trained himself to be independent of external assistance, we accept the universal tradition of Greece to the effect that Gorgias, triumphant over all the countless ills incident to extreme old age, would bid his hearers propound any questions they pleased for him to answer.