Pythagoreanism

Pythagoreanism refers to the philosophical doctrine of the early Pythagorean school represented by Pythagoras in Greece and formed in the ancient Greek colonial city-state of Croton in the southern part of the Italian peninsula. Like the Elia school, it was committed to the search for abstract principles, which promoted the formation and development of the ancient Greek idealist philosophy, preaching the idea of the immortality of the soul and reincarnation, believing that the soul is immortal, and the human soul can migrate to other organisms, and can appear repeatedly, so that all living things are related by blood. Given that there are abstract things in the world besides material beings, and find that there is some abstract quantitative relationship in everything.

Further Information
https://en.wikipedia.org/wiki/Pythagoreanism

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