Greece & Rome · c. 530–350 BCE
Pythagoreanism
The cosmos is an ordered harmony structured by number, and the immortal soul is purified by understanding that order.
What gives the world its order, and how should the soul live?
Around 530 BCE Pythagoras left Samos for Croton in southern Italy and founded a community that was at once a religious brotherhood, a way of life and a circle of inquiry. Discoveries such as the numerical ratios of musical concords suggested that mathematics could reveal hidden structure in nature.
If the octave, fifth and fourth correspond to the ratios 2:1, 3:2 and 4:3, then beauty and order are, at bottom, number. Philolaus argued that nothing could be known without number, since knowing means grasping limit and proportion. A soul that studies this order becomes ordered itself.
- Number and proportion are the principles of all things.
- The soul is immortal and passes into new bodies.
- Philosophy is a way of life that purifies the soul.
Through Plato it passed on the conviction that reality is mathematically structured, an idea that still drives physics; it was revived as Neopythagoreanism from the 1st century BCE.
Thinkers
c. 570–495 BCEPythagorasFounder of a philosophical and religious brotherhood at Crotonc. 470–385 BCEPhilolausPythagorean whose book first set out the school’s doctrinesKey texts
Where it came from
Grew out ofMilesian schoolThe Pythagoreans kept the Ionian search for a single principle of the cosmos but found it in number and harmony rather than in a material stuff.
What it led to
Carried on byPlatonismPlato took from the Pythagoreans the immortal, reincarnating soul and the conviction that mathematics reveals the structure of reality.Carried on by
NeoplatonismLater Neoplatonists such as Iamblichus and Proclus revered Pythagoras and gave number a central place in the unfolding of reality.
On the record
The Pythagorean school lists only one primary text, Philolaus’ fragments.
Pythagoras wrote nothing, and books later circulated under his name are judged forgeries. Philolaus’ On Nature was probably the first book written by a Pythagorean; about eleven of its fragments are accepted as genuine.
Sources: Stanford Encyclopedia of Philosophy, “Pythagoras” · Stanford Encyclopedia of Philosophy, “Philolaus”