During dinner, Little Johnny's mother catches him feeding the dog under the table. "Johnny," she says sternly. "You know very well that you're not supposed to feed the dog at the table!"

"I'm sorry, Mom." Johnny replies.

"All is well," his mother replies. "Now, do you know why we have that rule in the house?"

Johnny muses for a moment, then replies, "I guess it's 'cause if the dog doesn't like the food I give him, the food'll get left on the floor and eventually rot."