This new civilization could not be achieved on the continent of Asia, and therefore a new theatre is prepared. "Europe may be called a continuation of Central Asia. It surpasses its Oriental neighbor in the advantage of having no internal mountain barrier to divide its north and south. Thus Europe has been able to develop itself more independently and freely in consequence of the number of its peninsular forms.... The three characteristic features in the formation of Europe that are the physical grounds of the development of its nations are its large extent of seaboard, its peninsular forms, and the number of its islands."[397] On the peninsula of Greece, on the shores of the Ægean and Ionian seas, there was freedom of movement, facility of intercourse with the surrounding nations, and inducements to maritime enterprise. These conditions were undoubtedly favorable to a higher development. "The inland sea, the magnificent river," says Cousin, "is the natural symbol of _movement_." These represent the activity of nature, and they become natural centres of progress. The sea is the highway of commerce, and commerce is the grand channel of ideas, the medium through which the knowledge acquired by one people can flow readily into other lands. Amid such conditions the mind awakes to activity, and the _period of youth_ commences. Awakening thought is first directed to the outer world, and attempts an explanation of its phenomena. Greek philosophy thus becomes, at its first appearance, a philosophy of nature, and the Ionian school was a school of physicists. Here the great names which appear at the dawn of mental activity are Thales, Anaximander, Anaximenes, Heraclites, and Diogenes. From the study of nature the human race advances to the study of man. The new school is a school of moral and mental philosophy, or, more correctly, of psychology and ethics, adorned by such immortal names as Socrates, Plato, and Aristotle. In Greece, philosophy, poetry, eloquence, the fine arts, were extensively cultivated. As this was an age of great activity of thought, so it was also an age of great political freedom. The government was in many respects a government of the people, a democracy. "Every thing, in fact, in Greece bears evidence of the preponderance of human personality, and the energy of individual character."[398] Grecian civilization represents the _youth_ of humanity. The results of this culture were carried to other lands by the conquests of Alexander, and subsequently by the conquering Romans. The poets, the architects, the sculptors, the historians, the philosophers of Greece, are still the guides and models of the men of thought and taste in all cultivated nations. The Greek is still, in a peculiar sense, the teacher of the world. 4. In Roman civilization we have the discipline of the will under social and civil law, the more perfect organization of society and of government, the development of the science of jurisprudence.