Eudoxus of Cnidus

Eudoxus of Cnidus (/ˈjuːdəksəs/; , Eúdoxos ho Knídios; c. 390 – c. 340 BC) was an ancient Greek astronomer, mathematician, physician, and lawmaker. He was a student of Archytas and Plato. Eudoxus is known for developing the theory of concentric spheres and making significant contributions to mathematics, including work on the method of exhaustion.

 Life 
Eudoxus was born in Cnidus (modern-day Yazıköy, Turkey) and was the son of Aeschines. His exact birth and death dates are uncertain, but sources suggest he reached his peak around the 103rd Olympiad (368–365 BC). He studied mathematics with Archytas and medicine with Philiston the Sicilian. At 23, he traveled to Athens to study with the followers of Socrates, and later to Egypt to further his studies in astronomy and mathematics.

Upon returning to Athens around 368 BC, Eudoxus possibly took charge of Plato's Academy. He later returned to Cnidus, where he built an observatory and continued teaching and writing.

 Contributions to Mathematics 
Eudoxus is regarded as one of the greatest classical Greek mathematicians, second only to Archimedes. He contributed to the development of the method of exhaustion, a precursor to integral calculus. His work laid the foundation for Euclid's Elements Book V, focusing on proportionality and providing a rigorous method to handle incommensurable magnitudes without using irrational numbers.

 Contributions to Astronomy 
In astronomy, Eudoxus is known for his theory of concentric spheres, which aimed to explain the motions of the planets using a series of nested spheres. His work influenced later astronomers, including Hipparchus and Ptolemy.

 Legacy 
Eudoxus's work influenced both ancient and modern mathematics and astronomy. The craters on Mars and the Moon named "Eudoxus" honor his contributions. An algebraic curve, the Kampyle of Eudoxus, is also named after him.

 References 

Sources
 Heath, Thomas. A History of Greek Mathematics. Oxford: Clarendon Press, 1921.
 Boyer, Carl B. A History of Mathematics. John Wiley & Sons, 1991.

Category:Ancient Greeks