Greek philosophy started in Miletus in Asia Minor (present day Turkey) with Thales. Miletus like other commercial cities of Ionia underwent tumultuous economic and political development in the 6th and 7th century BC. Initially power was in the hands of landowners. They were replaced by plutocracy of merchants who in turn were replaced by the Tyrants who achieved power with the help of democratic parties.
Thales together with Anaximander and Anaximene formed the Milesian school of thought. The Milesian philosophy was scientific and rationalistic.
Thales successfully predicted the solar eclipse which had taken place in 585 BC and that is why historians put him at that time in the chronological map. Thales got the knowledge of Astronomy from Lydia which had cultural contacts with the Babylonians. Babylonian astronomers have discovered that eclipse occurred in a cycle of 19 years. Thales was supposed to have travelled to Egypt and thence got the knowledge of geometry to Greece. Thales believed that the primal substance of this universe is water. Everything is made of water and eventually decomposes in it. He believed that magnets have soul as it attract iron. Today Thales philosophy and science might seem to be crude but it was a big stimulus to thought and observation and was empirical.
Anaximander the second philosopher from Mellitus who was 64 years of age in 546 BC agreed with Thales that all things originated from single primal substance but that is not water as Thales believed. Anaximander believed that the primary substance is infinite, eternal and ageless. It encompasses the entire world and every thing is derivative of it. He makes an important and remarkable statement:
“Into that from which things take rise they pass away once more, as is ordained, for they make reparation and satisfaction to one another for their injustice according to the ordering of time”
Anaximander reasoned that the primal substance cannot be water or any other element. If that would be the case it would subjugate all other elements (fire, air, earth etc.) and would be the only element left and others would cease to exist. So he concluded that all other elements are modified form of primal substance.Anaximander, though not as respected in antiquity as the other two philosophers, has earned reverence of modern day philosopher for his prescient thoughts.
Anaximene the third proponent of Milesian school must have lived before 496 BC as that year Miletus was destroyed by the Persian in the course of suppression of Ionian revolt. Anaximene said that the primal substance is air and all other elements are modified from it. Water is condensed air, earth is con densed water, stone is condensed earth and the soul is rarified air.
The Milesian school is very important, not for what they have achieved, but what they have attempted. It was untouched by the religious movement connected with Bacchus and Orpheus. The speculation of Thales, Anaximander & Anaximene are to be regarded as the scientific hypothesis and seldom show any intrusion of anthromorphic desires and moral ideas which prevailed in Greece at that time.