When Aristotle returned to Athens to close the great era of philosophic vigor, being near the temple of Apollo Lyceus, his school was known as the Lyceum, and here every morning and evening he addressed a numerous body of scholars. Among the acute and impressible Greeks nearly all objects, however ideal in their original treatment, subsequently received a practical form. As the imaginative sublimities of their poets became embodied in glorious sculptures, so the theories of their early philosophy were wrought out politically, or gave way to cumulative mathematical demonstration. Plato, in dialogues and dissertations, philosophized with all the fervor of an artist; while the method of Aristotle was strictly scientific in the minute as well as enlarged sense of the word. To the first, philosophy was a speciality which engrossed a protracted life; but the latter treated not only of natural science, and natural history as well, but he also wrote on politics, general history, and criticism, so that it may be said truly that he epitomized the entire knowledge of the Greeks. The age of Plato was an age of ideals; but with Aristotle the realistic age had dawned. Pericles had begun to take part in public affairs one year before the birth of Socrates; Olynthus was taken by Philip of Macedon the very year in which Plato died. This intermediate period of one hundred and twenty years was all occupied with some ideal of beauty, wisdom, or freedom, in the persons of poets, architects, sculptors, painters, statesmen, who were striving to realize it, dreaming of it, or sporting with it to amaze and bewilder their fellow-men. But the name of Aristotle, as that of Philip, is a signal that concentrated organizing power has appeared in the realms of thought and action, and that the coming age requires a philosophical expounder who shall in his own career govern the old and represent the new. It was at Athens that Aristotle collected all the treasures of scientific facts the conquered nations could contribute, and wrote there the great works which were still young in their influence when the Macedonian madman had long since crumbled into dust.