National Geographic Daily News
The Last Supper.   A painting from a series of Bible illustrations by James Tissot

A painting depicts the Last Supper, whose 13th guest was Judas, who betrayed Jesus.

Photograph by Brooklyn Museum/Corbis

John Roach

for National Geographic

Published September 12, 2013

It's Friday the 13th, and millions of people are on edge, fearing a calamity with personal or global repercussions-a broken leg, a stock market crash, or the trigger pulled for World War III.

Why all the anxiety? In short, because the fear is ingrained in Western culture, according to experts. (Get more Friday the 13th facts.)

"If nobody bothered to teach us about these negative taboo superstitions like Friday the 13th, we might in fact all be better off," said Stuart Vyse, a professor of psychology at Connecticut College in New London.

People who harbor a Friday the 13th superstition might have triskaidekaphobia, or fear of the number 13, and often pass on their belief to their children, he noted. Popular culture's obsession with the fear-think the Friday the 13th horror films and even this story-helps keep it alive, added Vyse, the author of Believing in Magic: The Psychology of Superstition.

Although superstitions can be arbitrary-a fear of ladders or black cats, for example-"once they are in the culture, we tend to honor them," said Thomas Gilovich, a professor of psychology at Cornell University in Ithaca, New York.

"You feel like if you are going to ignore it, you are tempting fate," he explained.

Origins Rooted in Religion

The trepidation surrounding Friday the 13th is rooted in religious beliefs surrounding 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 and was already a source of anxiety, Vyse said. (Read more: "Friday the 13th Superstitions Rooted in Bible and More.")

The two fears merged, resulting "in this sort of double whammy of 13 fallingon an already nervous day," he said.

The taboo against the number 13 spread with Christianity and into non-Christian areas, noted Phillips Stevens, Jr., an associate professor of anthropology at the University of Buffalo in New York."It became extremely widespread through the Euro-American world, embedded in culture, [and] extremely persistent," he said.

More interesting, he noted, is why people associate any Friday the 13th with bad luck. The answer, he said, has to do with what he calls principles of "magical thinking" found in cultures around the world.

One of these principles involves things or actions-if they "resemble other things in any way of resemblance-shape or sound or odor or color-people tend to think those things are related and in a causal way," he explained.

In this framework, there were 13 people present at the Last Supper, so anything connected to the number 13 from then on is bad luck.

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.

According to Fernsler, 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.")

Fernsler said 13's association with bad luck "has to do with just being a little beyond completeness. The number becomes restless or squirmy."

Then there's Friday. Not only was Christ crucified on that day, but some biblical scholars believe Eve tempted Adam with the forbidden fruit on a Friday. Perhaps most significant is a belief that Abel was slain by his brother Cain on Friday the 13th.

Crippling Impact

On Friday the 13th, some people are so crippled by fear that they lock themselves inside; others will have no choice but to grit their teeth and nervously muster through the day.

Nevertheless, many people will refuse to fly, buy a house, or act on a hot stock tip, inactions that noticeably slow economic activity, according to Donald Dossey, a folklore historian and founder of the Stress Management Center and Phobia Institute in Asheville, North Carolina. (Read about animal phobias.)

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

To overcome the fear, Vyse said, people should take small steps outside their comfort zone. Those who are afraid to leave the house could consider meeting a close friend at a cozy cafe, for example.

"Try some small thing that they would be reluctant to do under normal circumstances and gradually experience, hopefully, no horrible thing happen when they push through and carry on," he said.

Chris Carias
Chris Carias

It's a dumb superstition. In latin-america (I'm Venezuelan, btw) it's Tuesday the 13th the unlucky day. And in Italy it's Friday the 17th. Everyone has a reason for it, no matter how  weird.

Peter Ateo
Peter Ateo

...because humans are IDIOTS. Next question...

Richard Fisher
Richard Fisher

I thought the Knights Templar got slaughtered on a Friday the 13th.

gutierrez maria
gutierrez maria

For the doubts should be day off and everyone to stay in house until Monday haha.

Frankie Millaire Pelletier
Frankie Millaire Pelletier

superstition, there are 13 moons in a year by the way....13 is a lucky number According to folklorists, there is no written evidence for a “Friday the 13th” superstition before the 19th century. The earliest known documented reference in English occurs in an 1869 biography of Gioachino Rossini:

Zahra R.
Zahra R.

I do not scare of number 13. My birthday is on 13th day and always the number 13 is a lucky number for me. I am really keen to know why lots of people have such fear of number 13? what was its source? 

in my idea it is an undue fear. It is just because we are dictating that thing for ourselves... all of the people just remember for themselves that "number 13 is bad, number 13 is bad..." then they will have an accident or sth like that.

By the way, yesterday was Friday 13th and I had just a happy day... I could do whatever I wanna do. I met my friends and had a fantastic meeting altogether. 

I have a suggestion, just change your attitude about number 13. it will works better for you :D

Mary Ann Lenc
Mary Ann Lenc

We draw to us what has settled in our heart and in our mind. We have the ability to keep negativity from finding a home in us. Remember this and be strong.

휘배 김
휘배 김

It makes good sense from this article I think.

Wylee Randall
Wylee Randall

I have no idea about Friday 13 until my fiance told me its a unlucky day . I just bought a new motorbike and had a accident today Friday 13 Sept 2013.I was knock down by a motorbike from behind speeding on the highway. I search on internet and discover Friday 13 is unlucky day and many people fear and talk about it. Before the accident my boss mention about accident and telling me to be careful.Coincidence my motorbike number plate is same with my Identity Card number.How you think?

G Morty Ortega Berger
G Morty Ortega Berger

Also, in Latin America, it's TUESDAY the 13th which is considered the unlucky day.

alexander maddatuang
alexander maddatuang

find the critical thinking and fight the worse perception
13 is a lucky number

Sarina Bamert
Sarina Bamert

With respect to this article, interesting that the 13 is a lucky number in Italy. 

Bobb R.
Bobb R.

ahhh religion strikes again

Ningisida Asyran
Ningisida Asyran

@Richard Fisher You are right, the author is snub,

read this..

"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"

this is as stupid argument as it can get, he should tell why all these are 12? and why 12 is complete?

Zahra R.
Zahra R.

p.s: thanks to the reading because it was helpful to find the source :)

Mike Owens
Mike Owens

I have heard this on the History Channel too. This is here this Friday the 13 scare comes from

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