If you derive comfort from stroking a rabbit's foot for good luck, or blow away an eyelash and make a wish, today might not be a good day for you. For those who have Friggatriskaidekaphobia, today is a particularly unpleasant day.
Why do some of us fear Friday 13th so much?Chair of the Department of Psychology at Cornell University, Thomas Gilovich says some people are afraid of this date because they link it to unpleasant things or events in their life.
"The mind is an associative system and if anything bad happens to you on Friday the 13th, the two will be forever associated in your mind and all those uneventful days in which the 13th fell on a Friday will be ignored."
Through psychology, Gilovish says, we can better understand the workings of superstitions and why people do certain things and behave in a particular way.
Between 17 and 21 million Americans have a phobia of Friday 13th, according to the Stress Management Center and Phobia Institute in North Carolina.
Gilovich stresses that there is no evidence whatsoever linking Friday 13th to bad luck or unpleasant events.
""People hold a number of beliefs without understanding the basis behind them or where they came from."
Apparently, interior designers and architects tend not to label the 13th floor of a building.
Psychology professor, Harvard University, Daniel Wegner has been researching into why some people see causal connections, especially when none exists.
"Our minds cause our actions and other things that happen in the world. It seems that we often believe we are powerful causal agents just because we happen to think of something before it happens!"
Often in sports, Wegner explains, people who think about certain things before they occur, can eventually believe that they were the driving force behind their occurrence. Wegner said:
"This is why sports fans fear going to the refrigerator because then their team might lose on TV. If they're not actively rooting for their team and thinking good thoughts, maybe they will be the ones who tip the balance towards the loss. Or at least, feel that they did."
According to the Dutch Centre for Insurance Statistics, fewer accidents and fires occur on Friday 13th, probably because people are more careful or just stay at home.