of the philosophers. Various inventions and discoveries are attributed to him, most famous of which is his prediction of an eclipse of 585 BCE. Modern scholars are fairly sure he was able to do this by consulting known Babylonian eclipse and lunar observations going back about 150 years, long enough to notice that eclipses recur after about 18 years. His activities also seem to have included star-observations and trigonometry, which he is credited with having founded, but the details of his theories are either lost or obscured by later legends about this early thinker who left no written record. He seems to have conceived of earth as flat and water-borne, and to have postulated that there must have been some first substance out of which the world arose, which he guesses is water. The next ancient Greek philosopher was Anaximander of Miletus who lived c. 550 BCE. The earth for Anaximander was still a cylinder circled by air and then fire "like the bark of a tree," which separated off at an early stage. Although his theory still echoes the early cosmologies, it is an attempt to explain the scheme in purely physical--in fact, in mathematical--terms. The heavenly bodies are all described as wheels; their visible light that we actually see is only a part of them, described as an axle, pipe, or vent. These vents opening or partially closing cause lunar variations. All these ideas did attempt to explain the universe in physical terms, though as yet there was only a vague theory as to why these things are so. Yet it is possible to see by Anaximander's "equilibrium" that the Greeks were beginning to be aware of gravity but still needed to put two and two together and recognize it explicitly. Through further study and thought the Greeks progressed towards a more concrete and accurate image of the earth and the heavens around it. Anaximines of Miletus (c. 525 BCE) refined the flat-earth idea, suggesting that all things are produced through a proce...
