Ptolemy
Early Life
Claudius Ptolemy was a mathematician, astronomer, geographer, and astrologer who lived in the city of Alexandria, in the Roman province of Egypt, during the 2nd century AD. He is best known for his scientific treatises, particularly the Almagest, which is a comprehensive treatise on astronomy, and the Geography, which is a detailed account of the known world.
Almagest
The Almagest is Ptolemy's most influential work and one of the most important scientific texts of all time. It is a comprehensive treatise on the astronomy of the classical age and includes a star catalogue containing 48 constellations, using the names we still use today.
Geography
In his Geography, Ptolemy provided a detailed account of the known world, including a systematic and comprehensive representation of the earth's surface. His work was based on the knowledge and data accumulated by earlier Greek and Roman geographers.
Astrology
Ptolemy also wrote a treatise on astrology, known as the Tetrabiblos, in which he attempted to adapt horoscopic astrology to the Aristotelian natural philosophy of his day.
Legacy
Ptolemy's works have had a profound influence on the development of Western science. His theories were widely accepted for over a thousand years and his works were considered the ultimate authority on astronomy and geography during the Middle Ages.