science

The Greek mathematician and philosopher Pythagoras lived with a cult of followers, who, while being vegetarians, avoided eating beans.

Like the Ancient Egyptians and Romans, they considered broad beans (also known as fava beans) a supernatural symbol of death. And due to a deadly allergy, the beans likely deserved their reputation.

According to Pliny, Pythagoreans believed that fava beans could contain the souls of the dead, since they were flesh-like. Due to their black-spotted flowers and hollow stems, some believers thought the plants connected earth and Hades, providing ladders for human souls. The beans’ association with reincarnation and the soul made eating fava beans close to cannibalism. Aristotle, writing earlier, went much further. One possible reason for the ban, he wrote, was that the bulbous shape of beans represented the entire universe.

https://www.atlasobscura.com/articles/favism-fava-beans