Pythagoras of Samos was an ancient Greek philosopher and mathematician best known for the Pythagorean theorem relating the sides of a right triangle. He founded a religious and philosophical community in Croton, southern Italy, whose followers, the Pythagoreans, believed that numbers were the fundamental principle underlying all things in the universe. He left no writings of his own, and much of what is known about him comes from later, sometimes contradictory, accounts by his followers.
