Greek philosophers
Eudoxos of Knidus
Eudoxos of Knidus was a Greek philosopher, mathematician and astronomer who was born about 408 BC in Knidus and died about 355 BC.
In philosophy, Eudoxos was a disciple of Plato, although they were to part on bad terms because he was to criticise his doctrine of ideas. In mathematics, he was a pupil of Archytas. In astronomy he was to study in Egypt. He is considered a member of the Ancient Academy.
His work has not survived but has been passed on, especially by Aratus. He founded an important mathematical school and observatory in his native Knido. Eudoxos was probably the first ancient author to base his thoughts on the universe on observation and other scientific methods.
He calculated the length of the solar year. He also considered 27 spheres around the Earth, around which the planets, the Moon and the Sun rotate. Aristotle subsequently built on this view. His geometrical views were later developed by Euclid and Theodosius of Bithynia.