The cosmological model of concentric or homocentric spheres, developed by Eudoxus, Callippus, and Aristotle, employed celestial spheres all of which had the same center, the Earth.
Philosophers and astronomers treated by Eudemus include Thales, Anaximander, Anaximenes, Oenopides, Eudoxus, and others.
Eudoxus of Cnidus (c. 408 BC – c. 355 BC), Greek astronomer and mathematician
Proclus also mentions that Menaechmus was taught by Eudoxus.
The discovery of a theory of ratios that does not assume commensurability is probably due to Eudoxus.
Sphaerics had its own shortcomings, for example Hipparchus had already introduced trigonometry, but Theodosius makes no use of it, perhaps because he was basing it on an earlier work by Eudoxus.
Scholars of the 19th century, however, argued against Hesiodic authorship, going so far as to assign the poem to the Hellenistic Period following the work of Eudoxus.
Eudoxus (under the Greek spelling of his name, Eudoxos) is the narrator of L. Sprague de Camp's historical novel The Golden Wind.