A farmer handed an empty bottle to his farm- hand and asked him to get him some grape juice from the juice stall down the road.
"What about money?" asked the man?
"Any fool can buy grape juice if he has money," replied the farmer. "The skillful man is he who can buy grape juice WITHOUT money!"
The farm-hand returned after a while. "Here's your grape juice." he said, handling over the bottle to his employer.
"Hey, but there's nothing in it!" said the farmer, peering disappointedly into the bottle.
"Why don't you try drinking it?" suggested the man. "Any fool can drink grape juice when it is there. It requires skill to drink it when it is NOT THERE!"