Ptolemy (AD 87–150)

Of all Roman intellectuals, Claudius Ptolemaeus, or Ptolemy, perhaps more than any other classical scholar, did the most to influence subsequent European notions of geography for the next millennium by dominating the popular and literary view of Earth throughout the Middle Ages. Little is known of his private life. Greek by birth, as were many scholars during the Roman Empire, he spent his career in Roman Egypt at the famous museum at Alexandria, then the epicenter of intellectual life. Ptolemy was, among other things, a mathematician, an astrologer, and an astronomer who studied optics and refraction; the Arabs later credited him with the invention of the astrolabe. His greatest work in this domain was the geocentric Almagest, or “Great Treatise” concerning the movement of the ...