Since man begins by looking outwards upon the external world and not inwards upon his own self, this fact too determines the character of the first period of Greek philosophy. It concerns itself solely with nature, with the external world, and only with man as a part of nature. It demands an explanation of nature. And this is the same as saying that it is cosmological. The {24} problems of man, of life, of human destiny, of ethics, are treated by it scantily, or not at all. It is not till the time of the Sophists that the Greek spirit turns inwards upon itself and begins to consider these problems, and with the emergence of that point of view we have passed from the first to the second period of Greek philosophy. Because the Ionic philosophers were all materialists they are also sometimes called Hylicists, from the Greek _hulé_ which means matter. Anaximander The next philosopher of the Ionic school is Anaximander. He was an exceedingly original and audacious thinker. He was probably born about 611 B.C. and died about 547. He was an inhabitant of Miletus, and is said to have been a disciple of Thales. It will be seen, thus, that he was a younger contemporary of Thales. He was born at the time that Thales was flourishing, and was about a generation younger. He was the first Greek to write a philosophic treatise, which however has been unfortunately lost. He was eminent for his astronomical and geographical knowledge, and in this connection was the first to construct a map. Details of his life are not known.