According to Pliny, after an oracle predicted Aeschylus would die from being hit by a falling house, the poet began “trusting himself only under the canopy of the heavens.” His precaution was futile; he was killed that day when hit by a tortoise dropped from the sky by a hungry eagle eager to crack open its shell.

“Among the greatest pieces of luck for high achievement is ordeal,” poet John Berryman told an interviewer in 1970, two years before his death. “Certain great artists can make out without it, Titian and others, but mostly you need ordeal. My idea is this: the artist is extremely lucky who is presented with the worst possible ordeal which will not actually kill him. At that point, he’s in business.”

Legend regarding the horseshoe as a lucky symbol holds that in the tenth century, while St. Dunstan was working in England as a farrier, the devil entered the forge and demanded his hooves be reshod. During the process, the future saint caused as much pain as he could, and the devil begged him to stop. Dunstan agreed—on the condition that Satan never enter a house where a horseshoe is on display.

Suetonius reported that Caligula often cheated when playing dice. The emperor once interrupted a game to go into the courtyard, where he spotted a group of rich knights passing. He had them arrested, stole their goods, then “resumed the game in high spirits, boasting that his luck had never been better.”

A twelfth-century-bc Chinese king consulted an oracle and was told his lucky charm would not be a tiger, dragon, bear, or leopard but rather a wise counselor. He soon came upon a sagacious old man fishing in the river and conscripted him into service. It is said the man’s virtue was such that he fished not with a hook but with a straight piece of iron; acknowledging his integrity, fish impaled themselves voluntarily.

A 2011 study found that Chinese consumers are charged more due to “superstitious manipulations” of retail prices—fives and sixes appear more often than unlucky fours, eights and nines more than unlucky sevens. “Retailers,” the study reported, “are the clear winners.”