THALES, in biography, a celebrated Greek philosopher, and the first of the wise men of Greece, born at Miletum about 640 years before the Christian sera. When he had acquired the usual learning of his country, he travelled into Asia and Egypt, to be instructed in geometry, as tron3my, and natural philosophy. On his return he became a teacher of yotith, and among his disciples, which were nume rous, were Anaximander, Anaximenes, and Pythagoras. Thales was the author of the Ionian sect of philosophers ; he was reckoned, by the best historia4, the father of Greek' philosophy, being the first that made any researches into natural knowledge and mathematics. He thought water was the principle of which all bodies in the universe are composed : that the world was the work of God, whom he re garded as omniscient, and beholding the secret thoughts in the heart of man. He maintained that real happiness consisted in health and knowledge : that the most ancient of beings is God, because he is un created ; that nothing is more beautiful than the world, because it is the work of God ; nothing more extensive than space, quicker than spirit, stronger than neces sity, wiser than time. He used to observe.
that we ought never to say that to any one which may be turned to our preju dice : and that we should live with our friends as with persons that may become our enemies. In geometry he was a con siderable inventor, as well as an improver, particularly in triangles and all the wri ters agree that he was the first, even in Egypt, who took the height of the pyra mids by the shadow. His knowledge and improvements in astronomy were very considerable. He divided the celestial sphere into five circles or zones ; the arctic and antarctic circles, the two tropi cal circles, and the equator. He observed the apparent diameter of the sun, which he made equal to half a degree; and form= ed the constellation of the Little Bear. He observed the nature and course of eclipses, and calculated them exactly ; one in particular, memorably recorded by Herodotus, as it happened on a day of battle between the Medes and Lydians, which Thaler had foretold; and,he divid ed the year into 365 days. He died at the age of ninety years, leaving behind him an excellent character, as a mathe matician, a philosopher, and moralist.