As you know, today is Friday the 13th. It's an arbitrary distinction, except that we humans have assigned a lot of importance to it. In fact, the Stress Management Center/Phobia Institute in Asheville, North Carolina, says that 17 million to 21 million Americans have a fear of Friday falling on the 13th so severe that it can be considered a phobia (if you are afflicted, call yourself a paraskevidekatriaphobe). But where did it start? Why is this date so associated with doom and gloom?
It has to do with a combination of reputations — of Friday itself and of the number 13. The view of 13 being an unlucky number is surprisingly widespread, around the world. Thanks to Judas, the last to arrive at the Last Supper, having 13 guests at a dinner table is considered bad luck. To the Norse Vikings, as well, having 13 guests is a no-no. Loki was the 13th guest at a banquet, where he killed the hero Balder. Hindus also consider 13 to be an unwanted numeral. This association with the number doesn't appear to be a coincidence. Before today's major world religions took hold, pagans considered the number in the opposite light — their calendar followed the moon's 13 cycles per year. When the 12-month solar calendar was introduced and paganism was condemned, 13 was deemed untrustworthy.
As for Friday being a day of bad luck, the associations are partly religious. It is thought that Eve tempted Adam with the apple on a Friday (though, of course, this would have been before days were named). Jesus was killed on Good Friday. The Temple of Solomon supposedly fell on a Friday as well. And though most of us cherish Fridays (yay, the weekend!), the British used to schedule it for hangings.
It is hard to tell when the two were combined, but evidence supports the bad reputation of Friday the 13th as a full-fledged phenomenon by the mid-19th century. And now, psychologists say, confirmation bias (whereby a belief in something makes a person look for reasons to justify it) has led us to believe it more and more. So as children, we grow up hearing that Friday the 13th is bad. Then, if something bad happens on that day, it is much more memorable than all the other good things that have happened, or even bad things that happened on other days.
Regardless of superstition, though, keep away from guys in hockey masks today, and definitely stay away from campsites on Crystal Lake, like, always.