Most people know that it’s bad luck to boast of good fortune. And many say that people (dating back to pagan times) knocked on wood as a way of acknowledging and securing favor with the gods who dwelled in trees, particularly if they had said something that drew attention to their good fortune. “He who talks too much of happiness summons grief” goes the old proverb. And there are a couple of theories as to why knocking on wood is supposed to help. One suggests that knocking on wood frightens bad spirits away or prevents them from hearing of your good fortune and taking it away. The other claims that the knocking acknowledges and calls to the good spirits who use their power to ensure you keep the good luck. So, just as example, if I were to hypothetically say something like, well, I don’t know, maybe “Luck: The Essential Guide is getting some very nice reviews, including one on the recently launched New Yorker blog called The Book Bench (click HERE),” I might knock on wood after I said it to make sure that the next person who writes a review doesn’t totally slam it. Just hypothetically, of course.