Eudoxus of Cnidus

He studied at the architectural, maintained close scientific contacts with Plato. Many traveled to Greece and Egypt, then started in his hometown of Knidos (at the south-west Asia Minor) school of mathematicians and astronomers.
Eudoxus of Cnidus one of the first attempted to construct a theory of planetary motion. He was famous hypothesis of moving celestial spheres. Accept the existence of 27 such spheres: one for the stars, three for the sun and moon, and four for Mercury, Venus, Mars, Jupiter and Saturn. Seneca says that Eudoxus of Cnidus first raised his knowledge of the motion of the planets in Greece. He is also credited with the introduction in the Greek calendar year, equal to 365.25 days. Eudoxus of Cnidus was the oldest surviving map of the starry sky, where the constellations were represented the figures of various animals and characters of Greek mythology; calculated the approximate amount of land that is considered a spherical.
The main merit Evdoksf Cnidus in mathematics include the establishment of the doctrine of values (in t.ch. and irrational numbers) and presentations on the basis of circumstantial evidence provision for determining the value of flatness phone. Works Eudoxus of Cnidus not reached our time.