Many superstitions date back to the medieval days when people believed that you could tell if your neighbor was a witch based her buoyancy in the local pond. But the “bad luck on Friday the 13th” thing doesn’t show up in lore until fairly recently. Why?
My guess is that someone was bored. I can just picture an older obnoxious brother who noticed two “unlucky” features coinciding on the calendar and deciding to terrorize his younger siblings with stories of all the horrid things that could happen on that rare day.
Both the number 13 and the day Friday developed reputations as being unlucky, but there is not much reference to this reputation until about 200 years ago. Starting in the 1800s, reports circulate about people who were afraid to begin a new task on a Friday, sometimes going to great lengths to begin on Thursday night so that any work on Friday would be merely a continuation of work and not a new beginning. (more…)