Here is a psychological theory that is not particularly popular as a true theory, but I think it is a very evocative idea anyhow. My own gut sense is that a few millenia in the past, humans weren't very much genetically different from today's, so about as many people were what we'd call schizophrenic (not nearly everybody, as Jaynes seems to suggest) but they were treated very differently. Perhaps there were non-genetic factors that led to higher or lower proportions of hallucinatory mental illnesses, though.

200 mg of ibuprofen does seem to reduce somewhat the symptoms of stiffness and (already mild) pain in my foot, but only for a few hours at a time, after which it comes right back. Actually getting a doctor's appointment is so annoying, but I think I will try to get one this time. I haven't had any particularly constistent symptoms recurring, but it's been like a year of occasional weird problems with my right shin/ankle/foot.