Friday the 13th

What is it about Friday the 13th we are supposed to be wary of? One explanation found on Wikipedia suggests that the superstition goes all the way back to the Middle Ages and has something to do with Jesus' last supper where there were 13 people present, the night before his death on Good Friday. If that's the case, I'm over it.

In fact I have never given the date a moment's thought since there are so many other days to be wary of, like April 15 or my next birthday. Those are some bad days. Still, better safe than sorry, and I'm willing to bet that almost everyone avoids walking under a ladder and having a back cat cross their path, despite not knowing why they do it. Ditto with this particular day. Just in case, I'll toss some salt over my left shoulder and be extra careful out there.