A Jackdaw, watching some Pigeons in a farmyard, was filled with envy when he saw how well they were fed, and determined to disguise himself as one of them, in order to secure a share of the good things they enjoyed. So he painted himself white from head to foot and joined the flock; and, so long as he was silent, they never suspected that he was not a pigeon like themselves. But one day he was unwise enough to start chattering, when they at once saw through his disguise and pecked him so unmercifully that he was glad to escape and join his own kind again. But the other jackdaws did not recognise him in his white dress, and would not let him feed with them, but drove him away: and so he became a homeless wanderer for his pains.
The Peasant and the Apple-tree
Utility is often the measure