569?-475? B.C.

Greek Philosopher and Mathematician

Despite the fact that he is famous for the discovery of the theorem that bears his name, Pythagoras did not view himself primarily as a mathematician; nor did the members of the society he founded, whose principles addressed nonscientific subjects such as reincarnation, or metempsychosis. Yet Pythagoras and his followers, the Pythagoreans, viewed the concept of the number as fundamental to the universe, and with their focus on numerical properties virtually inaugurated the serious study of mathematics in the West.

The son of Mnesarchus, a merchant from Tyre (now in Lebanon), and his wife Pythias, Pythagoras grew up in Samos, Ionia, on what is now the western part of Turkey. His father's profession gave him reason to travel widely, and apparently the boy accompanied him on trips as far away as Italy. During his youth, Pythagoras fell under the influence of...