A small plane was carrying three passengers over a mountain range -- an old man, his grandson, and an eminent scientist.

Suddenly, the pilot burst into the cabin, saying 'The engines have all failed! Grab a parachute and jump from the plane!' With this, the pilot opened the cabin door and leapt out with his parachute.

To their dismay, the 3 passengers discovered only 2 parachutes were left in the cabin!

The Eminent Scientist took a pack, saying 'I'm sorry you two, but I won a Nobel Prize, I am the head of several intellectual Think Tanks -- honestly, I'm worth more to society than either of you'. The Eminent Scientist leapt from the plane.

The Old Man turned to his grandson and said, 'My dear boy, take the last parachute. I've had a good life. Yours has just begun.'

'Don't worry, Grandpa' said the young boy, 'that guy just jumped out the plane with my backpack.'