How Friday the 13th Works

Like many human beliefs, the fear of Friday the 13th (known as paraskevidekatriaphobia) isn't exactly grounded in scientific logic. But the really strange thing is that most of the people who believe the day is unlucky offer no explanation at all, logical or illogical. As with most superstitions, people fear Friday the 13th for its own sake, without any need for background information.

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