He asked a friend to hide just inside his barn, above the doorway, and gave him three small bags of rice. He then invited each son inside, one at a time.
The first son, after feeling the rice bag fall on his head, drew his sword and cut the bag in half before it hit the ground.
The second son halved the bag even before it hit his head.
The third son, sensing something amiss, declined to enter the barn - and so earned his father's sword.
Photos taken November 2005 in Tian Tan, Temple of Heaven, Beijing
Story taken from Body Mind Mastery (Creating Success In Sport and Life), Dan Millman