§ 49. The century at which we have now arrived in our survey--the fourth before Christ--was eminently the age of political theories devised by philosophers in their studies; and they give us the conclusions to which able thinkers had come, after the varying conflicts which had tested the capacities of all the existing States to attain peace with plenty at home, or power abroad. The Athenian supremacy had broken down; the Spartan, a still more complete _hegemony_, as the Greeks called it, had gone to pieces, not so much by the shock of the Theban military power, as by its own inherent defects. Epaminondas has passed across the political sky, a splendid meteor, but leaving only a brief track of brilliancy which faded into night. [Sidenote: Greece and Persia.] [Sidenote: Theoretical politics.] And in every generation, if the military efficiency of Persia grew weaker, her financial supremacy became more and more apparent. In the face of all these brilliant essays and signal failures, in the face of the acknowledged intellectual supremacy of the Greeks, coupled with their continued exhibitions of political impotence in foreign policy, it was fully to be expected that Greek thinkers should discuss the causes of these contrasts, and endeavour to ascertain the laws of public happiness and the conditions of public strength. And so there were a series of essays, of which several remain, on the Greek State and its proper internal regulation, and a series of solutions for the practical difficulties of the day, especially the external dangers to which the Hellenic world was exposed. These documents form the main body of the splendid prose Literature of the Attic Restoration, as I have elsewhere called it[118:1], and of the period which closed with the actual solution of the difficulties in foreign politics by the famous Philip of Macedon[118:2]. [Sidenote: Inestimable even to the practical historian.] The historian of Greece must evidently take into account these speculations, though they be not strictly history; but the facts can hardly be understood and appreciated without the inestimable comments of the greatest thinkers and writers whom the country produced. [Sidenote: Plato.] [Sidenote: Xenophon.] [Sidenote: Aristotle.]