Thales c.620-c.555BC
Greek natural philosopher, astronomer and geometer

He came from Miletus on mainland Ionia, Asia Minor, as did his intellectual successors Anaximander and Anaximenes. He is traditionally the founder of Greek, and therefore European, philosophy, and is important for having proposed the first natural cosmology, identifying water as the original substance and (literally) the basis of the universe. He seems to have had wide-ranging practical and intellectual interests, with a reputation as a politician, engineer, geometer and astronomer. He is supposed to have visited Egypt and developed his interest in land-surveying and astronomical techniques there, to have predicted accurately a solar eclipse in 585BC, and to have proposed a federation of the Ionian cities of the Aegean. He was included in the traditional canon of 'Seven Wise Men', and attracted various apocryphal anecdotes, for example as the original absent-minded professor who would fall into a well while watching the stars. He left no writings, except possibly a nautical star-guide.