Watch out for black cats, avoid mirrors and ladders and, by all means, don't spill the salt.
As most people probably already realize, today is Friday the 13th, a date commonly associated with bad luck.
For the next several hours, millions of superstitious individuals across the country will hold their breath anticipating misfortune. Others will avoid leaving the house altogether, refusing to drive, shop or work on the ill-fated day.
But whether you're a true triskaidekaphobe (a person with an irrational fear of Friday the 13th, also called a paraskevidekatriaphobe) or just mildly suspicious, it's probably a good idea to know just where your trepidation comes from.
Though it's hard to pinpoint the exact origins of any superstition, several Internet sites are devoted to the history of the Friday the 13th legend. And most list the same possible origins of the rumoured curse. One of the more lucid sites is David Emery's urbanlegends.about.
According to a biography on the Web site, Emery is a freelance journalist, as well as a staff writer for both a TV sitcom and a satirical newspaper. He has a bachelor's degree in philosophy from Portland (Or.) State University and completed graduate studies in philosophy and the classics at the University of Texas at Austin. He apparently has a particular interest in modern folklore and founded urbanlegends.about.com to "debunk, deconstruct and discuss the most popular tall tales and hoaxes in circulation."
While the Web site explores everything from e-mail hoaxes to dubious quotes, three pages are devoted to the history of Friday the 13th.
According to the site, the superstition is derived from myths about both Fridays and the number 13.
Fridays, for example, are hailed as a particularly significant day in the Christian tradition. Obviously, there is Good Friday, the day Jesus Christ was crucified. But according to Christian lore, Adam and Eve also supposedly ate the forbidden fruit on a Friday, the Great Flood started on a Friday, the builders of the Tower of Babel were tongue-tied on a Friday and the Temple of Solomon was destroyed on a Friday.
Of course, the Bible doesn't specifically note many these events occurring on Fridays, and Emery explains some of the tradition may have stemmed from the fact that pre-Christian pagan cultures hailed Friday as holy days. The word "Friday" is, in fact, derived from a Norse deity who was worshipped on the sixth day of the week and who represented marriage and fertility. Fridays in the early Norse culture were associated with love and considered a good day for weddings.
Over time, however, mythology transformed the Norse fertility goddess into a witch, and Fridays became an unholy Sabbath. Incidentally, the goddess' sacred animal was a cat, which may explain the legendary connection between witches and cats, as well as the superstition about black cats heralding bad luck.
In addition to the legendary significance of Fridays, the sixth day of the week also was execution day in ancient Rome and later Hangman's Day in Britain, according the Emery's Web site.
The number 13 also has mythological and religious symbolism.
Both the Hindus and Vikings reportedly had a myth in which 12 gods were invited to a gathering and Loki, the god of mischief, crashed the party and incited a riot. Tradition in both cultures holds that 13 people at a dinner party is bad luck and will end in the death of the party-goers.
Following in that vein, the Last Supper in Christian tradition hosted 13 people and one betrayed Christ, resulting in the crucifixion.
The number 13 also has been associated with death in other cultures. The ancient Egyptians, for example, believed life unfolded in 12 stages, and the 13th stage was death. The Egyptians considered death a part of their ultimate journey and looked forward to the spiritual transformation ‹ thus 13 was not an unlucky number in their culture ‹ but like so many others, the tradition warped through time and cultures, eventually associating the number 13 with a more negative and fearful interpretation of death, Emery writes.
Finally, Emery suggests the number 13 may have an unlucky connotation because of its association with the lunar calendar (there are 13 lunar cycles in a year) and with femininity (women have 13 menstrual cycles in a year).
Then, there's the event that ties the two superstitions together.
"Though it's clear that superstitions associating Fridays and the number 13 with misfortune date back to the ancient times, some sources assign the precise origin of the black spot on the day itself, Friday the 13th, to a specific historical event," adds Emery.
It was on Friday, Oct. 13, 1307, that France's King Philip IV had the Knights Templar rounded up for torture and execution. The Knights Templar were an order of warriors within the Roman Catholic Church who banded together to protect Christian travellers visiting Jerusalem in the centuries after the Crusades. The Knights eventually became a rich, powerful ‹ and allegedly corrupt order within the church and were executed for heresy.
So, who knows?
The date may be forever cursed by one event that occurred nearly 700 years ago, or by a series of cosmic coincidences.
Or it may be a figment of human beings' collective imaginations.