The following is NOT a trick question; however, I have heard two different answers for it.
How many legs would a dog have if we called the dog's tail a leg?
- The answer is clearly 5- since 4+1=5. Duh.
- Calling the tail a leg does not make it a leg. A dog has 4 legs. Duh.
- I have seen people on either side not be able to even understand the other side's point.
- This question has been attributed to Abraham Lincoln; however, just as Bogart never said Play it again Sam and Kirk never said Beam me up Scotty, Lincoln (likely) never said calling a tail a leg does not make it a leg (though he might have said Play it again Sam or Beam me up Scotty). See this interesting and serious post for information on what Lincoln said.
- In our terminology Lincoln's point was that definitions should conform to reality and if they do not then it is the definitions that are wrong. I suspect he would not have liked the Banach-Tarski Pardox.