The Pythagorean moral philosophy is related to Orphic mysticism.
It is difficult to distinguish which elements can be ascribed to the Orphics and which to the Pythagoreans.
Central to this ethical philosophy was the concept of metempsychosis; the transmigration of the soul.
Here we find a certain similarity to Hinduism. Belief in metempsychosis also entailed abstinence from animal products.
The Pythagorean ethics are set out in the Golden Verses.