Thales

Thales (625?–546? B.C.), first known Greek philosopher. His ideas are known to us through the writings of others, such as the Greek philosopher Aristotle. Thales approached subjects through what he could scrutinize and logically reason about them—an approach quite different from the Greek tradition of explanations through supernaturally directed myths. Because of this approach, he is considered the first philosopher in the Western tradition. His observations led him to the conclusion that water was the cornerstone of all things on earth. He also introduced geometry to Greece. His school of thought is called either Milesian (based on Miletus, his birth place) or Ionian (based on Ionia, city-state of Greece in which Miletus was located).

See also: Pre-Socratic philosophy.