A fifteenth-century Tunisian sex manual relates that “a big beard denotes a small mind” and tells of a long-bearded man who reads a quote to this effect on the back of a book. Afraid of being seen as a fool, he tries to trim his beard by setting it on fire but burns it off entirely. He then writes on the book below the quote, “These words are entirely true. I, who am now writing this, have proved their truth.”

To cure madness in “men fond of literature,” medical encyclopedist Aulus Cornelius Celsus suggests reading aloud to them “incorrectly, if that’s what gets them going; for by correcting you they begin to divert their mind.”

A CIA report declassified in 2000 revealed concerns about extrasensory perception during the space race in the 1960s: a Russian newspaper argued that cosmonauts “get together mentally with each other easier than with people on Earth,” while a Chicago Tribune columnist worried that the Soviets “may be the first to put a human thought in orbit or achieve mind-to-mind communication with men on the moon.”

For the treatment of “delirium and mania combined with shameless behavior,” ninth-century Persian polymath al-Razi offered a remedy by medical theorist Simʿun: “Bathe the patient’s head with a decoction of elecampane and sheep’s trotters, pour milk over him, put dung upon him, make him snuff sweet violet oil and breast milk, and feed him anything that is cold, fatty, and fills and moistens the brain.”