An anxious father said to his son's school principal: "I want you to stop my son gambling. All he ever seems to want to do all day is bet, bet, bet." "Leave it to me," said the principal. A week later, the principal phoned the father and said: "I think I've cured him." "How?" asked the father. "Well, I saw him looking at my beard and then he said, 'I bet that's a false beard.' 'How much do you want to bet on it?' I asked him. And he said, 'Five dollars.'" "What happened?" asked the father. "Well…