A jackal was about to be eaten by a lion. The jackal pleaded, "No, please! You mustn't eat me! It would be a grave mistake. If you eat me, it will be terrible—a disaster, the end of the world!"
The lion, puzzled, asked, "How so? How could eating you possibly end the world?"
"Because," replied the jackal, "if you eat me, it will be the end of my world!"