The Eleusinian and Orphic mysteries strongly influenced the development of Pythagoreanism with their beliefs on the soul and their practices in initiation, rituals and secrecy. Both these mysteries, as well as the Pythagoreans, believed in the immortal soul that cycles through the process of transmigration until the soul becomes pure enough to unite with the divine. The Pythagoreans adopted the initiation ceremony from the Eleusinian mysteries as well as many traditions and rituals. While the Pythagoreans adopted many of the rituals and traditions, they also developed their own in conjunction with the studies of mathematics, astronomy, music and metaphysics. The Pythagoreans also adopted and expanded upon the traditional secrecy policies of the mysteries. The central beliefs of the mystery cults were at the central beliefs of the Pythagoreans, but the Pythagoraeans developed and expanded (making minor changes to) the mystery cults using studies in education and philosophy.
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