THE ASS AND THE WATCH-DOG 
A watch-dog in a village was barking all night to keep thieves off from his master's house. An ass, who observed this, thought that the dog amused himself by barking. So he brayed all night. When the day dawned, the owner of the ass thought the poor animal had been suffering from some disorder. Therefore he sent for the village doctor, and laid the case before him.
The doctor examined the animal closely, and said, "Friend, you must brand this ass forthwith, else he will soon go into fits and die."
The ass said, "I assure you nothing is wrong with me; I simply amused myself last night."
"Oh, no," said the inexorable leech; "I know what the wily brute means. He would rather die, and make you the loser, than be branded and recover his health."
So they bound the ass with ropes, and branded him all over with red-hot irons. Some time after the ass moved out to see how the village had fared during his illness. The dog asked why he had been branded. The ass narrated the story. Quoth the dog, "He that mistakes work for amusement must pay for his error."