Thales of Miletus
ΘαλῆςThe first to ask what everything is made of
Thales is the hinge on which Western thought turns from myth to inquiry. He proposed that beneath the apparent chaos of the world lies a single underlying substance — and that it could be named, argued for, and disputed. The content of his answer (water) matters far less than the form of his question: what is the arche, the originating principle of all things?
All things arise from water and return to it. Earth floats on water; moisture is the seed of life and the medium of change. The claim is wrong — but it is the right kind of wrong: a single, natural, testable cause rather than a god's will.
Tradition credits Thales with predicting the solar eclipse of 585 BCE, drawing on Babylonian records of lunar-solar cycles. Whether literal or legendary, it marks a new ambition: the heavens run on periods a human mind can compute.
He is said to have measured the height of pyramids by their shadows and a ship's distance from shore by triangulation. The 'Theorem of Thales' (an angle inscribed in a semicircle is right) abstracts surveying into proof.
Thales did not invent from nothing. Egyptian land-survey and Babylonian astronomy supplied centuries of data and technique. His leap was to demand reasons, not just recipes — to turn know-how into know-why.
Aristotle names Thales the first physiologos — the first to seek a natural account of nature. Not because his answer was correct, but because he replaced 'the gods did it' with 'there is a principle, and we can argue about it.' That move — substituting argument for authority — is the seed of science.
Every later 'theory of everything', from atoms to fields to strings, is a descendant of Thales' single question. The unity of nature became a research program.
Whether or not Thales truly predicted the eclipse of 585 BCE, the legend encodes the real revolution: the heavens are not omens to be feared but periods to be computed. Prophecy becomes forecast.