Founder of the school of mathematics in Alexandria, Euclid likely received previous mathematical training from the Platonic Academy in Athens. He is known for having written the Elements, a fundamental work on geometry, numbers, elementary algebra, optics, etc., and one of the oldest known treatises on plane and solid geometry. This treatise, which contains thirteen books, illustrates in a systematic way a set of theorems based on a system of axioms and postulates, and their proofs. Unfortunately, except for the Elements, most of Euclid's work, which was translated into several languages, was lost. Euclid (~300 B.C.)