Add Yahoo as a preferred source to see more of our stories on Google. It's Friday the 13th — and some people will be wary of ladders, black cats and broken mirrors. (Getty Images) (Getty Images) Maybe ...

Maybe you have to tap the plane three times as you board. Maybe you can't watch your beloved Eagles play without wearing your lucky (and desperately in need of washing) green socks. Maybe you're ...

Source: Kane Icarus Lynch, used with permission. In their quest to understand human behavior and belief, psychologists have studied magical thinking and superstitious behavior for over a century. They ...