Two men, representing two forces, had guided the city during those decades. On the one hand there was Aristides, called the Just--inflexible, incorruptible, impersonal and generous; on the other, Themistocles--precocious and wild as a boy; profligate as a youth and young man; ambitious, unscrupulous and cruel; a genius; a patriot; without moral sense. The policy of Aristides, despite his so-called democratic reforms, was conservative; he persuaded Greece, by sound arguments, to the side of Athens: he was for Athens doing her duty by Greece, and remaining content. That of Themistocles was that she should aim at empire by any means: should make herself a sea-power with a view to dominating the Greek world. Oh, to begin with, doubtless with a view to holding back the Persians; and so far his policy was sane enough; but his was not the kind of mind in which an ambitious idea fails to develop in ambitious and greedy directions; and that of mastery of the seas was an idea that could not help developing fatally. He had been banished for his corruption in 471; but he had set Athens on blue water, and bequeathed to her his policy. Henceforward she was to make for supremacy, never counting the moral cost. She attacked the islands at her pleasure, conquered them, and often treated the conquered with vile cruelty. The _Seven against Thebes_ was directed by Aeschylus against the Themistoclean, and in support of the Aristidean, policy. Imperialistic ambitions, fast ripening in that third decade of the fifth century, were opposed by the Messenger of the Gods.