Into the early modern period, the word bug referred to a phantom in the dark; a 1535 translation of the Bible made for Henry VIII came to be known as the Bug Bible for its rendering of Psalm 91:5 as “Thou shalt not nede to be afrayed of eny bugges by night.” The word was changed to terrors in later editions, but the original sense still colors the common bedtime warning against letting bedbugs bite.

In August 2018 data scientist David Bamman examined how authors recently interviewed in the New York Times’ By the Book column answered the question “What’s on your nightstand?” Women mentioned male and female authors almost equally; men mentioned male authors more than 79 percent of the time. “Don’t read in bed,” advised Fran Lebowitz. “It’s too stimulating. Watch TV instead. It’s boring.”

Asked whether it was night or day that first emerged when the universe came into existence, sixth-century-bc Greek philosopher Thales of Miletus replied, “Night, earlier by a day.”

In 2005 the British Cheese Board attempted to dispel the idea that eating cheese before bed causes nightmares. No evidence of this “evil myth” was reported among two hundred volunteers, though eating Stilton was found to lead to “crazy” dreams, while eating cheddar often led to dreams of celebrities. “We hope that people will think positively about eating cheese before bed,” said the board secretary.

Astronomers theorizing the existence of small moons orbiting larger moons have proposed calling them “moonmoons.” The planet Kepler-1625b, which has a Neptune-sized moon distantly orbiting it, was cited as “sort of the best-case scenario for a moonmoon.”

Psychologists at the University of California recognized a lack of sleep “as a social repellent” and its effect contagious: “People who come in contact with a sleep-deprived individual, even through a brief one-minute interaction, feel lonelier themselves as a result.”

Emily and Charlotte Brontë, insomniacs both, would walk together in circles around the dining room table until they were tired enough to sleep. When Emily died and Charlotte suffered alone, her insomnia worsened; she added to her route, often wandering down neighborhood streets and into the cemetery until daybreak.

Poet Edward Fairfax kept a 1621 account of his daughter Helen’s terrible nightmares, describing an incident in which she complained about a demonic white cat that “has been long upon me and drawn my breath.” The cat, she said, “has left in my mouth and throat so filthy a smell that it does poison me.”

Setting grim tales during nighttime was critiqued as a cliché in 1594 by Thomas Nashe. “When any poet would describe a horrible tragical accident,” he wrote, “to add the more probability and credence unto it, he dismally begins to tell how it was dark night when it was done.”