Key-man in the history of philosophy and mathematics, he is indirectly known above all for the influence of his thought, while the steps of his biography can be rebuilt with difficulty.
We know that he was born in the isle of Samo between the 580 and the 570 B.C. where he lived till about 40 years. At this age he left his country and moved to Calabria in Crotone that was the centre of an important medical school. Here he founded his school where both men and womenwere allowed, a unique event in the Greek world. His teachings did non set out to transmit theorical knowledge but they wanted to support a life style and an inner purification that had both mystical and scientifical aspects.
Pitagora thought that the structure of reality was based on numbers: in his opinion they were the principle of all things; the main law that acted them consisted in the opposition between prime numbers and odds and by this law derived all the oppositions between physical world and moral one (limited/unlimited, one/many, male/female, good/evil and so on).
Starting from numbers one could deduce all the exact laws that rule every relationship in the universe. From here, he gave attention to the various sciences that took Pitagora to study through arithmetic and geometry, getting as in the famous theorem about the right-angled triangle to demostrations based on abstact considerations.
Arithmetic and geometry took him to the study of acustic (thanks to which he discovered the principal musical intervals) and to those astronomy. Arithmetic, geometry, astronomy and music were linked by an only conception and numbers expressed the deep harmony of reality.