THALESMiletus, approx. 640 - 546 B.C.
One of the Seven Sages of Ancient Greece. He became rich by trading salt, he traveled to Egypt, from which he introduced the use of the so-called Egyptian fractions, i.e. those having numerator one, to the homeland. He measured the height of the great Egyptian pyramids from their shadow and determined the causes of the annual floods of the Nile. He discovered the attraction of light bodies by electricity. He predicted the solar eclipse of May 28, 585 BC. and is considered the founder of Theoretical Geometry. He took water as the beginning of "everything".