The Academic Questions, Treatise De Finibus, and Tusculan Disputations, of M.T. Cicero, With a Sketch of the Greek Philosophers Mentioned by Cicero

Charmides

Cicero's Tusculan Disputations Also, Treatises On The Nature Of The Gods, And On The Commonwealth

Gorgias

Meno

Plutarch's Morals

Political fragments of Archytas, Charondas, Zaleucus, and other ancient Pythagoreans, preserved by Stobæus