In a fancy Paris restaurant, there is a magical wish-granting mirror. But it only grants wishes if you tell the truth -- if you lie, you disappear.
One day, a blonde, a brunette, and a redhead enter the restaurant and decide to try out the mirror.
The brunette goes first.
"I think I'm the smartest woman on earth."
"POOF!" She disappears.
The redhead goes up to try. "I think I'm the prettiest woman on earth."
"POOF!" She disappears. The blonde goes up.