Three friends, a mathematician, a physicist, and a biologist, are stranded on a desert island. They have run out of food and water and are beginning to lose hope of being rescued.
One day, as they are wandering the beach in search of anything that might help them survive, they stumble upon a magic lamp buried in the sand. They rub the lamp and out pops a genie.
The genie tells them that he can grant each of them one wish, but it must be something that is physically possible. The mathematician goes first and says, "I wish for a ship to come and rescue us from this island." The genie nods and, poof, a ship appears on the horizon and the mathematician is saved.
The physicist goes next and says, "I wish for a helicopter to come and rescue us from this island." The genie nods again, poof, a helicopter appears overhead and the physicist is saved.
Finally, it's the biologist's turn. He thinks for a moment and then says, "I wish for the mathematician and physicist to come back to the island."