It was in Athens, and among the Athenians that most of the movement was carried on. The principal state in Greece besides Athens then was Sparta. The Spartans devoted themselves mainly to warlike and allied arts, while the Athenians devoted themselves mainly to the beautification of Athens; though they were careful to guard it adequately by maintaining an excellent navy, surrounding the city with high walls, and building two long parallel walls from Athens to Piræus, its seaport. It would be out of place in a book like this to attempt any description or discussion of the various phases of the intellectual activities that rose with such startling quickness, and developed into such important movements, during the century and a half that followed the Persian wars; especially as this has already been done by many scholars, in many languages, and at many times. A very brief and elementary statement may, however, be made, for the purpose of illustrating the influence of invention on history. The main characteristic of the movement as a whole and of every one of the various channels which it followed, was originality. No such perception of beauty had ever been evidenced before; no such conceptions of logic, philosophy or science. Accompanying these was a conception of free government equally original. Whether the government of Athens was the cause of the intellectual rise, or the intellectual rise was the cause of the government, may safely be left to scholars to debate; for the purposes of the present discussion, it seems sufficient that they co-existed and had together a powerful influence on history. The greatest genius that guided the intellectual forces of the Athenians in the matter of government was that of Pericles, who ruled their minds by pure force of argument and persuasion, from about 445 to 431 B. C. Athens and her subject cities formed a virtual empire, small in extent, but powerful in influence; though in form it was a democracy. In some ways it was the most perfect democracy that ever has existed even to this day; for not only was every citizen available for office, but he was expected to take active part in deciding public measures, and to be really qualified to hold office.