Ptolemy

a celebrated astronomer. A native of Egypt. Dates are uncertain, but he is known to have flourished in Alexandria about 139 A. D. He wrote in Greek, the language of learning at that time. He was an eminent writer on geography and mathematics, but in many respects his teachings were far less scientific than the earlier ones they replaced. He is especially noted for his views of the movements of the sun, moon, and stars. According to Ptolemy, the earth is the center of the universe. The sun, moon, and stars are set in crystal globes which turn around the earth daily carrying the heavenly bodies around with them. This theory would be interesting merely as a curiosity, were it not that the so-called "Ptolemaic System" was adopted and held by the authorities of the church as in accordance with the Bible; for Joshua commanded the sun to stand still and it obeyed him. See Joshua x:12, 13, and Habakkuk iii:11. To doubt the Ptolemaic system was to doubt the Bible and scorn the teachings of the church. Ptolemy was an accepted authority until the middle of the fifteenth century. See Copernicus; Galileo