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Find out how the date got its unlucky reputation and how even nonbelievers may be influenced by our collective triskaidekaphobia.

As if October wasn’t spooky enough, this year the creepiest month also features the return of Friday the 13th.

October 13 is the second ill-fated Friday to fall in 2017. And while January the 13th wasn’t especially sinister, it seems that no matter how many such moments pass us by, the dreaded day continues to inspire unease and fears of misfortune.

There’s no logical reason to fear the occasional coincidence of any day and date. But Friday the 13th can still have noticeable impacts. Sometimes we create them in our own minds—for good and ill.


Jane Risen, a behavioral scientist at the University of Chicago Booth School of Business, has found that superstitions can influence even nonbelievers. In one study, Risen found that people who identify as superstitious and non-superstitious both believe a bad outcome is more likely when they’ve been jinxed, such as by stating they definitely won’t get into a car accident.

“Generally speaking, I find that this occurs because the bad outcome springs to mind and is imagined more clearly following the jinx,” she explains. “People use the ease of imagining something as a cue to its likelihood.”

This kind of thinking may be more widespread on Friday the 13th: “Even if I don’t actively believe, just that fact that Friday the 13th exists as a known cultural element means that I entertain it as a possibility,” she says. When otherwise unremarkable events occur on that date, we tend to notice.

“That adds a bit more fuel to this intuition, makes it feel a bit more true, even when you recognize that it’s not true.”

Fortunately, Risen’s research also suggests a way to reverse the curse: perform rituals that ward off bad luck, like knocking on wood or throwing salt. Risen found that some people use them even when they don’t actively believe, and when tested, both types of people reported benefits from such acts.

“We find that people who jinx themselves don’t think the bad outcome is especially likely if they knock down on wood,” Risen says. “So, the ritual does seem to help manage their concern.”

In that way, simply being aware of superstitions may help to instill a sense of order in a world of random and uncontrollable worries, according to Rebecca Borah, a professor of English at the University of Cincinnati.

“When you have rules and you know how to play by them, it always seems a lot easier,” she told National Geographic in 2014. On Friday the 13th, “we don’t do anything too scary today, or double-check that there’s enough gas in the car, or whatever it might be.”

“Some people may even stay at home—although statistically, most accidents happen in the home, so that may not be the best strategy.”


Where does a fear of Friday the 13th come from in the first place?

It’s difficult to pin down the origins and evolution of a superstition. But Stuart Vyse, a professor of psychology at Connecticut College in New London, said our fear of Friday the 13th may be rooted in religious beliefssurrounding the 13th guest at the Last Supper—Judas, the apostle said to have betrayed Jesus—and the crucifixion of Jesus on a Friday, which was known as hangman’s day.

The combination of those factors produced a “sort of double whammy of 13 falling on an already nervous day,” Vyse explained in 2014. Some biblical scholars also believe Eve tempted Adam with the forbidden fruit on a Friday, and that Abel was slain by his brother Cain on Friday the 13th.

Curiously, Spain appears to have escaped this malevolent marriage of number and day. Friday the 13th is no cause for alarm there, and instead Tuesday the 13th is the year’s most dangerous date.

Other experts suspect even older roots for this form of triskaidekaphobia. Thomas Fernsler, an associate policy scientist in the Mathematics and Science Education Resource Center at the University of Delaware in Newark, said the number 13 suffers because of its position after 12.

Numerologists consider 12 a “complete” number. There are 12 months in a year, 12 signs of the zodiac, 12 gods of Olympus, 12 labors of Hercules, 12 tribes of Israel, and 12 apostles of Jesus. (See “Lost Gospel Revealed; Says Jesus Asked Judas to Betray Him.”)

The number 13’s association with bad luck “has to do with just being a little beyond completeness. “The number becomes restless or squirmy,” he noted in 2013.

Numerology may also explain why Italians have no qualms about Friday the 13th but fear the 17th instead. The Roman numeral XVII can be rearranged to spell “VIXI,” which translated from Latin means “my life is over.”


Arbitrary though they may be, superstitions like fears of ladders, black cats, or “unlucky” numbers are incredibly persistent.

“Once they are in the culture, we tend to honor them,” Thomas Gilovich, a professor of psychology at Cornell University in Ithaca, New York, explained in 2013. “You feel like if you are going to ignore it, you are tempting fate.”


Black cats are also seen as unlucky in many European cultures.


Some people, whether by determination or necessity, grit their teeth and nervously get through the day. Others really do act differently on Friday the 13th.

They may refuse to travel, buy a house, or act on a hot stock tip, and these inactions can noticeably slow economic activity, according to the lateDonald Dossey, a folklore historian and founder of the Stress Management Center and Phobia Institute who spoke with National Geographic in 2013. (Read about animal phobias.)

“It’s been estimated that $800 or $900 million [U.S.] is lost in business on this day, because people will not fly or do business they normally would do,” he said.

Ironically, people heeding their superstitious fears may be passing up a chance to spend the day in a slightly less dangerous world. A 2008 study by the Dutch Centre for Insurance Statistics revealed that fewer traffic accidents occur on Friday the 13th than on other Fridays. Reports of fire and theft also dropped, the study found.

Soon enough, this Friday the 13th will end, and even the most superstitious among us can rest easy—at least until April 13, 2018.

By Brian Handwerk for NationalGeographic