Nasruddin's relative showed up for dinner, bringing a duck.
Nasruddin made duck soup.
"Delicious!" said Nasruddin's relative.
The next day Nasruddin added water to the leftover soup.
A knock at the door: it was a friend of his relative, and he stayed for dinner. "Good soup!" the man said.
The next day Nasruddin added water to the leftover soup again.
Another knock: a friend of the friend of his relative. When Nasruddin served the soup, the man frowned. "It's not very good."
"What do you expect?" Nasruddin shouted. "It's the soup of the soup of the soup of the duck!"
Inspired by: The Sufis by Idries Shah, free to read online at the Idries Shah Foundation.
Notes: This is on p. 75 of the book.