An old king has three sons. He isn’t sure who should succeed him and so he decides to test them. He gives each of them some money and tells them that, whoever manages to have his own palace filled completely in three days would succeed his throne.
The first son thinks for a while, then looks for and pays the city garbage collector to dump the city’s garbage in his palace for the next three days.
The second son thinks for a while, then gets his servants to buy the cheapest grass they can find and fill up his palace for the next three days.
The third son doesn’t think much about the task. He goes about the next three days as usual.
At the end of the third day, the king visits his first son. Though there is a huge pile of garbage waste in his palace, it doesn’t fill the place completely. The king visits his second son. Though there is a huge stack of rotting grass in his palace, it doesn’t fill the place completely.
When the king visits his third son, he is shocked that nothing additional has been bought to fill the palace. “There’s still so much emptiness,” the king exclaims.
“Oh no, no, no,” the third son explains, “my palace is filled full with air. It has always been filled so. So why waste the money to cramp up the place with useless and extra stuff? And if you really want me to buy something, I could have bought scented candles to fill the palace with light and fragrance. Or pay a group of musician to fill the palace with music and happiness. That’s how I would have spent the money.”
The king approves of this explanation and chooses the third son to be the successor.