Thales of Miletus

Thales of Miletus (c. 626/623 – c. 548/545 BC) was an Ancient Greek pre-Socratic philosopher from Miletus in Ionia. He is recognized as one of the Seven Sages of Greece and is often regarded as the first philosopher in the Greek tradition, initiating a shift from mythological explanations to natural philosophy and deductive reasoning. Thales's central cosmological thesis was that water is the arche, the fundamental substance from which all things originate. He also proposed that the Earth floated on water. In mathematics, he is credited with introducing theoretical geometry to Greece and is associated with theorems bearing his name, such as the one concerning a right triangle inscribed in a circle. As an astronomer, he is said to have predicted a solar eclipse and made observations about celestial bodies. Thales was also known for his practical wisdom and engineering feats, demonstrating that philosophy could have practical applications.