The history of Greek PHILOSOPHY, like that of Greek poetry and history, began in Asia Minor. The earliest philosopher of distinction was THALES of Miletus, who was born about B.C. 640, and died in 554 at the age of 90. He was the founder of the IONIC school of philosophy, and to him were traced the first beginnings of geometry and astronomy. The main doctrine of his philosophical system was, that water, or fluid substance was the single original element from which everything came and into which everything returned. ANAXIMANDER, the successor of Thales in the Ionic school, lived from B.C. 610 to 547. He was distinguished for his knowledge of astronomy and geography, and is said to have been the first to introduce the use of the sun-dial into Greece. ANAXIMENES, the third in the series of the Ionian philosophers, lived a little later than Anaximander. He endeavoured, like Thales, to derive the origin of all material things from a single element; and, according to his theory, air was the source of life. A new path was struck out by ANAXAGORAS Of Clazomenae, the most illustrious of the Ionic philosophers. He came to Athens in 480 B.C., where he continued to teach for thirty years, numbering among his hearers Pericles, Socrates, and Euripides. He abandoned the system of his predecessors, and, instead of regarding some elementary form of matter as the origin of all things, he conceived a supreme mind or intelligence, distinct from the visible world, to have imparted form and order to the chaos of nature. These innovations afforded the Athenians a pretext for indicting Anaxagoras of impiety, though it is probable that his connexion with Pericles was the real cause of that proceeding (see Ch. IX). It was only through the influence and eloquence of Pericles that he was not put to death; but he was sentenced to pay a fine of five talents and quit Athens. The philosopher retired to Lampsacus, where he died at the age of 72. The second school of Greek philosophy was the ELEATIC which derived its name from Elea or Velia, a Greek colony on the western coast of Southern Italy. It was founded by XENOPHANES of Colophon, who fled to Elea on the conquest of his native land by the Persians. He conceived the whole of nature to be God.