The term triskaidekaphobia describes a specific phobia associated with the number 13. The link has arisen because so many unlucky events in history have become connected with this number. Triskaidekaphobia affects millions of Americans and Europeans (but not Asians). In Asian cultures, the number 13 is considered lucky and so they are not afflicted by this irrational fear.
The word triskaidekaphobia can be broken down into three Greek words. In translation, the term means “the number three” plus “the number ten” equals “fear”.
The origin of this fear of misfortune arising around the number 13 is thought to date from at least Babylonian times, circa 1780 BC. Archaeological excavations have unearthed numbered lists from this era which miss out item number 13. However, this may just have been a contemporary clerical error. Most explanations of this superstition (or phobia) use much later events to illustrate its possible origins.
One common theory is that relating to Jesus Christ and the Last Supper. Christians believe that Judas (who betrayed Jesus to the authorities) was the thirteenth person to attend the Last Supper. However, no references to this theory have been found in any documents prior to the 12th century. Where the number 13 and Friday coincide, many people consider this to be an especially inauspicious day. This is because the crucifixion of Christ took place on a Friday.
There is the very practical theory that having 13 guests to dinner makes for an uncomfortable and difficult seating plan. If you only have 12 guests, the invited party divides easily into twos (for matchmaking purposes), into threes (for having small intimate discussions) or even into fours (ideal for playing card games like bridge).
Research published in the British Medical Journal in 1993 links Friday the 13th to an increase in car accidents. The study by Scanlon et al. showed that “the risk of hospital admission as a result of a transport accident may be increased by as much as 52%. Staying at home is recommended.”
John Roach writing for the National Geographic in 2004, interviewed Donald Dossey, founder of the Stress Management Center and Phobia Institute in Asheville, North Carolina. Mr Dossey estimated that between $800 and $900 million is loss to American businesses whenever Friday 13th occurs. These losses are due to people staying at home rather than going to work, or delaying completing business deals.
Richard Wiseman, a British psychologist who specializes in research on lucky and unlucky people, has questioned people in relation to their superstitious beliefs and Friday the 13th. He was testing his theory that people make their own luck. In a study of 4000 people, he first asked participants to state whether they considered themselves to be lucky or unlucky people. He then asked whether they dreaded the number 13 and/or Friday.
The study found that of those who considered themselves to be lucky only 22% of them dreaded Friday and/or the number 13. This compared to 55% of those who considered themselves to be unlucky.
Triskaidekaphobia may be a superstitious belief rather than a true phobia. However, for those who suffer from it the symptoms and beliefs are very real. The symptoms can range from mild nervousness through to a full-blown panic attack.