Tomorrow is Friday the 13^th. While the dreaded combination evokes feelings of unease even among non-believers, for the superstitious, it is the unluckiest day of the year. Their intense fear, dubbed friggatriskaidekaphobia, leads to symptoms that range from mild anxiety to a nagging suspicion of bad luck to full-blown panic attacks. While some of the trepidation can be attributed to the namesake movie series, the day’s ill-fated reputation was well-established long before Jason Voorhees, the film’s hockey-masked villain, first appeared on the big screen in 1980.

Some experts think it all starts with the fear of 13 or Triskaidekaphobia. According to University of Delaware associate policy professor Thomas Fernsler, 13 is considered unlucky because it follows the “perfect” number 12. There are, after all, 12 months in a year, 12 zodiac signs, 12 tribes of Israel, 12 apostles of Jesus, etcetera.

Folklore historian Donald Dossey attributes the number’s bad reputation to a myth from the time when the Vikings occupied Scandinavia. A dozen gods were enjoying a quiet dinner party in Valhalla, the mythological Norse heaven, when Loki, the god of mischief, walked in uninvited. According to the legend, he instigated Hoder, the blind god of darkness, into killing Balder, the god of joy and gladness. Dorsey says to this day, Nordic residents avoid dinner parties with 13 guests, for fear that one of them will end up dead.

Legend has it that US President Franklin D. Roosevelt hated the date so much that he never traveled on the 13th nor invited just 13 guests to a meal. American author and humorist Mark Twain became a believer after he was left starving as the 13th guest at a party that had catered food for only 12. The French even go as far as 'renting' a special 14th guest, or quatorzieme, to avert bad luck.

Friday has its own set of problems. According to the Bible, Jesus was crucified on this day. While the date was not the 13^th, it was shortly after his final meal, the “Last Supper,” which featured 13 guests, including Judas Iscariot, the apostle who betrayed Jesus to the Sanhedrin for 30 silver coins. Some biblical scholars think that it was on a Friday that Eve tempted Adam with the forbidden fruit, though the date is unknown. The only historical event believed to have occurred on Friday the 13^th is the slaying of Adam and Eve’s son Abel by his brother Cain. A more recent tragedy was the sinking of the Costa Concordia, the world’s largest passenger ship, on Friday, January 13^th, 2012.

Experts estimate that American businesses lose as much as $900 million every time the 13th falls on a Friday because many people avoid getting on airplanes or making substantial purchases like a home or car. Though bad for the economy, the irrational fear does benefit non-believers. Airlines often offer discounted fares and many retail stores have special deals to attract customers to stores. So, instead of cowering in fear, use the dreaded day to firm up your summer travel or buy the game you have been eyeing for so long.

Happy Friday The 13th

Resources: wikipedia.org, businessinsider.com, history.com