This is a good point. If you went with the "simplest" explanation then which one do you pick: 1. The patients humors are out of whack. The treatment is bloodle

This is a good point. If you went with the "simplest" explanation then which one do you pick: 1. The patients humors are out of whack. The treatment is bloodletting. 2. The patient has a complex infection involving many physiological systems like immune system, foreign bacteria, gut flora, etc. The treatment is rest and administration of a lab engineered antibiotic for weeks. Or: 1. The patient is possessed by a Djinn/Demon/spirit and needs an exorcism from a priest/shaman/imam. 2. The patient suffers from mental illness which is difficult to describe let alone treat. Treatment will be years, if not decades, of a mix of therapy, lifestyle changes, and medication. Sadly, these attitudes still exist, even in the industrialized West. I often visit /r/paranormal because I have a thing for ghost stories and sometimes there's a posting about "possession" which is very clearly about a mentally ill person. When I point this out and ask why this person isn't getting proper care, I'm downvoted to -5 near instantly. Yes, that's right, the guy saying "This isn't a demon, this poor woman needs proper medical help," gets argued with like its the 13th century.