Pythagoras
Ancient Greek · Europe · 570 to 495 BCE
Greek teacher who led a community devoted to number, harmony and a disciplined way of life. He is credited with the idea that reality has a mathematical order.
What it is
Pythagoras was a Greek teacher born on the island of Samos around 570 BCE, who later moved to the city of Croton in southern Italy and founded a community there. He is famous as the man behind the Pythagorean theorem, but there is wide agreement that very little is certain about what he actually taught.
He is known for the teaching that the soul is immortal and is reborn in new bodies, and for the way of life of the community around him. Later writers turned him into a near-divine figure, and many works were forged in his name, so historians try to separate the real teacher from the legend.
The main ideas
- The soul is reborn. The soul is immortal and, after death, enters a new body, human or animal. This is the teaching most securely tied to him.
- A shared way of life. He gathered followers into a community with its own rules of conduct and ritual, which is why he is described as much as a religious teacher as a philosopher.
- Order in the world. In the later Pythagorean tradition, number and harmony give the world its order. How much of this goes back to Pythagoras himself is disputed.
What it looks like in practice
Picture someone who adopts a few fixed daily habits and a shared meal with friends, on the belief that how they live now shapes what they become. Pythagoras is remembered as a teacher of a way of life of this kind, though what the rules actually were is uncertain. This is an illustration of the idea, not a report of what he taught.
Books and moments
- His own writings do not survive. Accounts of him come from later writers, and some works were forged in his name.
Questions and criticism
- Mathematician or religious teacher? The popular picture is of a mathematician, but the earliest evidence suggests that in his own day his fame rested on religion and the soul, not on mathematics.
- Did he prove the theorem? The relation between the sides of a right triangle was known earlier in Mesopotamia and Egypt, and whether Pythagoras proved it is doubtful.
- What did he really teach? Because the earliest evidence is thin and later writers glorified him, much of what is said about him may belong to his followers.
Close neighbours
Heraclitus and Parmenides were near-contemporaries who asked different questions about what the world is. Plato later took up Pythagorean ideas about the soul and number.
Written by epchē in our own words, and checked against independent sources on 9 October 2026. The sources are listed below.
Who they connect to
Influenced
- Parmenides · Ancient writers connect Parmenides with a Pythagorean circle in southern Italy. (scholars disagree about this link)
- Plato · Plato took over the Pythagorean interest in mathematics and in the soul's fate.
Other Ancient Greek thinkers
- Thales of Miletus · 624 to 546 BCE
- Anaximander · 610 to 546 BCE
- Anaximenes · 586 to 526 BCE
- Xenophanes · 570 to 475 BCE
- Heraclitus · 535 to 475 BCE
- Parmenides · 515 to 450 BCE
- Anaxagoras · 500 to 428 BCE
- Empedocles · 494 to 434 BCE
- Zeno of Elea · 490 to 430 BCE
- Leucippus · 480 to 420 BCE
Sources we used
- Pythagoras · Stanford Encyclopedia of Philosophy, read on 9 October 2026
- Pythagoras · New World Encyclopedia, read on 9 October 2026
- Pythagoras · Wikipedia, read on 9 October 2026