Pythagoras of Samos (about 569 BC - about 475 BC)

Pythagoras was a Greek philosopher who made important developments in mathematics, astronomy, and the theory of music. The theorem now known as Pythagoras's theorem was known to the Babylonians 1000 years earlier but he may have been the first to prove it.

Pythagoras of Samos is often described as the first pure mathematician. He is an extremely important figure in the development of mathematics. Pythagoras of Samos, c.560-c.480 BC, was a Greek philosopher and religious leader who was responsible for important developments in the history of mathematics, astronomy, and the theory of music. He migrated to Croton and founded a philosophical and religious school there that attracted many followers. Because no reliable contemporary records survive, and because the school practiced both secrecy and communalism, the contributions of Pythagoras himself and those of his followers cannot be distinguished. Pythagoreans believed that all relations could be reduced to number relations ("all things are numbers"). This generalization stemmed from certain observations in music, mathematics, and astronomy. The Pythagoreans noticed that vibrating strings produce harmonious tones when the ratios of the lengths of the strings are whole numbers, and that these ratios could be extended to other instruments. They knew, as did the Egyptians before them, that any triangle whose sides were in the ratio 3:4:5 was a right-angled triangle. The so-called Pythagorean theorem, that the square of the hypotenuse of a right triangle is equal to the sum of the squares of the other two sides, may have been known in Babylonia, where Pythagoras traveled in his youth; the Pythagoreans, however, are usually credited with the first proof of this theorem. In astronomy, the Pythagoreans were well aware of the periodic numerical relations of heavenly bodies. The CELESTIAL SPHERES of the planets were thought to produce a harmony called the music of the spheres. Pythagoreans believed that the earth itself was in motion. The most important discovery of this school--which upset Greek mathematics, as well as the Pythagoreans' own belief that whole numbers and their ratios could account for geometrical properties--was the incommensurability of the diagonal of a square with its side. This result showed the existence of IRRATIONAL NUMBERS. Whereas much of the Pythagorean doctrine that has survived consists of numerology and number mysticism, the influence of the idea that the world can be understood through mathematics was extremely important to the development of science and mathematics.

By: einstein - 2007-05-18 14:49:06