The lying shepherd
The lying shepherd is a fable attributed to Aesop. In Spain it is sometimes erroneously mentioned as the story of "Peter and the Wolf", by to Sergéi Prokófiev's homonymous musical tale (1936). Synopsis
A young shepherd who tended his flock of sheep in the vicinity of a small village. One day he makes a joke to the locals, so he goes to the site in alarm, shouting that he had met a wolf, and that his sheep were in danger. This worried all the inhabitants, who were ready to help him. Running they followed him to the spot where he had spotted the supposed wolf, but found only the mockery of the young man. Angry with the lie they returned to the town. The wolf, however, did appear to the shepherd one day, and he returned to the village to ask the help of the neighbors but, because they imagined that it was another heavy joke of the shepherd, they decided not to help him. And so the wolf ate all the sheep and the shepherd. Moral
"You should always tell the truth, because if you always lie when you tell the truth nobody will believe you."
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