Hypatia of Alexandria

Hypatia of Alexandria was born in the year 370. She was the daughter of the philosopher Theon, who directed the Museum of Alexandria, a center of Greek culture and learning that included the Great Library and many schools. Hypatia studied with her father, and with other philosophers, including Plutarch the Younger. Eventually she became a teacher at the Neoplatonist school of philosophy. She became the director of this school in 400.

She probably wrote on mathematics, astronomy and philosophy, including about the motions of the planets, about number theory and about conic sections. Some of her works, now lost to history, include The Astronomical Canon, ACommentary on the Arithmetica of Diophantus and A Commentary on the Conics of Apollonious. She edited the third book of her father's Commentary on the Almagest of Ptolemy.

Remarkable for a woman at the time, she dressed in philosophers robes rather than female dress and drove in her own chariot through the streets of the city. She was a pagan in an era in which the Christian church had increasingly grown in power and influence. In the same style of Socrates, over eight centuries earlier, she would publicly interpret Plato, Aristotle, or the works of any other philosopher to those who wished to hear her.

Historical accounts maintain that Hypatia was prudent and virtuous in her private behavior. Her advice was well sought after, including by Orestes, the governor of Alexandria, himself a pagan. Hypatia corresponded with and hosted scholars from others cities. Synesius, Bishop of Ptolemais, was one of her correspondents and he visited her frequently. She was a popular lecturer, drawing students from many parts of the Roman Empire.

Her accomplishments in engineering were remarkable as well. From the little historical data about Hypatia that survives, it appears that she invented the plane astrolabe, the graduated brass hydrometer and the hydroscope, with Synesius. Synesius would later use what he learned at Hypatia’s feet to help formulate the Christian doctrine of the Trinity.