Fava beans contain small amounts of L-Dopa which increases dopamine and can give some people more vivid dreams. So that could explain the “souls of the dead” belief – could be enough people dreamt of dead relatives to believe they’d seen their spirits.
I once worked on the top floor of a building (11 stories) in which small spiders would sometimes rappel down from the ceiling tiles. This freaked out an arachniphobic coworker.
I thought he’d find it comforting to know that spiders are carnivores and he should be more worried about whatever it was they were finding to eat up there. Strangely, this information did not ease his fears. Go figure.
Fava beans contain small amounts of L-Dopa which increases dopamine and can give some people more vivid dreams. So that could explain the “souls of the dead” belief – could be enough people dreamt of dead relatives to believe they’d seen their spirits.