writes "It certainly doesnâ(TM)t change anything. Sure, knocking on wood might feel good, but youâ(TM)re just as likely to fail that test, catch that flu, and crash that bike as you were before. And yet, thereâ(TM)s something so satisfying and comforting about doing it, something that eradicates that creeping feeling of panic that overcomes you after you tempt fate and jinx yourself.
According to a group of researchers from the University of Chicago, there may be some deep psychological roots behind why knocking on wood and other superstitious rituals, like spitting or throwing salt, may be so prevalent cross-culturally."Link to Original Source