Pythagoras

Biography

Born on the island of Samos, travelled extensively through Egypt and Babylon, studying secret knowledge. Around 530 BC he founded a community in Croton (southern Italy), where he and his disciples conducted scientific and philosophical research. The school was closed after a revolt, and Pythagoras himself likely died in Metapontum.

Key discoveries

• Pythagorean theorem: a² + b² = c² for a right-angled triangle – one of the most famous mathematical statements.
• Doctrine of numerical ratios in music: the intervals of the octave, perfect fifth and perfect fourth correspond to ratios 2:1, 3:2 and 4:3.
• Discovery of incommensurability (irrational numbers) exemplified by the diagonal of a square.
• The concept of 'harmony of the spheres' – the idea that celestial bodies move according to mathematical laws and produce an unheard music.