43.  E.g., Hippias in Protag. 337C, where he says that men are related (συγγενεῖς, οἰκείους) by nature, not by law, and that the law is a tyrant of men that does much violence contrary to nature (παρὰ τὴν φύσιν).

44.  Cf. Alcidamas frag., cited infra on Aristotle’s theory of slavery, and Ar. Pol. i. 3. 1253b20-23; Lycophron (pseudo-Plut. Pro. Nob. 18. 2) denies the reality of the distinction between noble and ill-born. Cf. also on Euripides, infra. On the development of the opposition to slavery in Greece, cf. Newman, Pol. of Arist., I, 139 ff.

45.  Diog. L. ix. 55: δίκη ὑπὲρ μισθοῦ. Cf. Diels, op. cit., II, 220, 231; Croiset, Hist. de la Litt. Gr., IV, 54. Souchon (op. cit., p. 23, n. 1) thinks that it may have taught the dignity of all labor. Cf. also Plato (Sophist 232 D): τὰ πρωταγόρεια ... περί τε πάλης καὶ τῶν ἄλλων τεχνῶν. Gomperz (Die Apologie der Heilkunst, p. 33) infers that Protagoras had published a Gesammtapologie der Künste. Cf. Pol. 299C, and Diog. L. ix. 8. 55.