Person 1: How smart are you? Person 2: Really smart Person 1: Ok. If you have 3 ghosts and take away 2 how many are left? Person 2: 1 ghost is left Person 1: Wrong! 0 ghosts are left because ghosts don't exist!!!
The Riddler???
One knight, a king and a queen went fishing. They each caught one fish so how did three fish end up in the bucket?
One "Knight"!!!