Theon was born in Alexandria in 335 and died in 405 AD. In the Hellenistic period Theon was a mathematician and astronomer.
He was the last director of the Library of Alexandria before its destruction and the director of the “Museum” (University) until it was closed down with an order from Emperor Theodosius in 391 AD. He was the father of the mathematician and philosopher, Hypatia.
The version of the Elements of Euclid in 364 was the crowning achievement of Theon and so people were learning geometry for 15 centuries. Theon also wrote arithmetic as well as “signs and examinations” of birds, about the rise of Sirius and the tides of the Nile.
Mary Roboti, Grade 2, 2nd Junior High School of Paralia