The aristocratic Athenian State was based upon land-ownership, slavery, and the entire freedom of the land-owning class from all but family and State duties, from all need of engaging in productive industry. So long as the chief wealth of the State consisted in land and its produce, so long the population was divided into two classes, the rich and the poor, and so long the former had little difficulty in keeping all power in its own hands. But no sooner did the growth of commerce throw wealth into the hands of a class that owned no land, and was not above engaging in industry, than this class began to claim a share in political power. There were now two wealthy classes, standing opposed to each other, a proud, conservative one, with "old wealth and worth," and a vain, radical one, with new wealth and wants, both bidding for the favor of the class that had little wealth, little worth, and many wants, and thus making it feel its importance. Such is the origin of Athenian democracy. It is the child of trade and productive industry. It owed its final consecration to the Persian Wars, and especially to the battle of Salamis, in which Athens was saved by her fleet, manned chiefly by marines (ἐπιβάται) from the lower classes, the upper classes, as we have seen, being trained only for land-service. Thus the battle of Salamis was not only a victory of Greece over Persia, but of foreign trade over home agriculture, of democracy over aristocracy. The fact that the Athenian democracy owed its origin to trade determined, in great measure, its history and tendencies. One of its many results was that it opened Athens to the influx of foreign men, foreign ideas, and foreign habits, not to speak of foreign gods, all of which tended to break up the old self-contained, carefully organized life of the people. In no department were their effects sooner or more clearly felt than in that of education. From about the date of the battle of Salamis, when the youthful Ionian, Anaxagoras, came to Athens, a succession of men of "advanced" ideas in art and science sought a field of action within her borders. Such a field, indeed, seemed purposely to have been left open for them by the State, which had provided no means of intellectual or moral education for its young citizens, after they passed under its care (see p. 87). Nothing was easier or more profitable than for these wise foreigners to constitute themselves public teachers, and fill the place which the State had left vacant. The State might occasionally object, and seek to punish one or another of them for corrupting of the youth by the promulgation of impious or otherwise dangerous ideas, as it did in the case of Anaxagoras; but their activity was too much in harmony with a tendency of the time,--a radical and individualistic tendency inseparable from democracy,--to be dispensed with altogether. Hence it was that, within a few years after the battle of Salamis, there flourished in Athens a