Superstition

I read a long article the other day on superstitions, which were defined as ...irrational fears of the unknown or the mysterious.  My mother was a country girl and as such had a great number of superstitions in her life.  The usual ones of crossing knives (unwise), spilling salt (need to throw a pinch over the left shoulder), and turning money over on seeing a new moon (highly beneficial).

Now, we all know that you shouldn't walk under a ladder, don't we, but do you know why?  I certainly didn't.  It seems that with a ladder leaning against a wall it makes a triangle, which represents the trinity.  Therefore to break the triangle you are breaking up the trinity which is considered bad luck.  It just makes sense to me not to push through anyhow.