Abraham Lincoln insisted on facts when a case was being presented to him. One day a committee set forth a case built up largely of "supposings." Mr. Lincoln asked them, "How many legs would a sheep have if you called its tail a leg?"

"Five," was the prompt answer.

"That is what I thought you would say," declared Lincoln, "but that isn't true; the sheep would only have four legs.  Calling a tail a leg doesn't make it one."