In Medieval times people believed that when mischievous sprites heard you wish for something they would make the opposite happen. Many show biz professionals still believe in them. I can attest to their existence. I have seen them in action.

One time, when I was attending an American Society for Training and Development International Conference and Exposition, a featured speaker began by saying that this opportunity to present in front of his/her colleagues was the completion of a lifelong dream. It was a bad choice of words. The audience responded enthusiastically. The sprites responding by freezing the presenter