Ahmes Papyrus

After the death of Pherecydes Pythagoras was impelled by Thales to turn towards the mystical Egyptian priests.Carrying with him a written recommendation by Polycrates to Pharaoh Amasis, Pythagoras achieved to be accepted as a student of the priests in Thebes. There he was initiated in all the Egyptian rituals and learned the Egyptian views about life and death. The Egyptians believed that many animals were sacred and their diet was as we would call it nowadays a vegeterian's diet.According to some historians Pythagoras had the chance to study the Achmes papyrus which dated back to the second millenium BC. This papyrus revealed through a mystical language some complex and perfectly developed mathematical theories which were unknown for the rest of the world.

After finishing his studies in Egypt he wandered all around the known world.At some point he became a student of Chaldean priests of Babylon who were masters of mysticism and astronomy. 

Carrying knowledge from all around the known world Pythagoras returned to Samos and became the teacher of Polycrates' son. However very soon their relations were worsened and Pythagoras left for Italy.