The Donkey in the Tiger-Skin

I recently came across a tiny book of Indian folk tales, costing only a buck, at a random thrift/antique shop. I just read through the first few tales and this third one caught my attention most, so thought I'd share. There's some saying that mentions "a nickel for your thoughts," but looks like a dollar can get you some advice as well:
In the city of Hastinapura there lived a washer by the name of Camphor-lover. Now Camphor had a donkey, a sickly feeble beast, nearer death than life from years of carrying cruelly crushing loads. So one day Camphor, in order to keep the old beast alive, covered him with the skin of a tiger so he would not be molested, and turned him loose in a forest near a lush field of grain. The owner of the field, seeing the tiger shape approaching his field turned and ran for his life. And thus it was that the old donkey settled down in the field to enjoy his finals days. Then one afternoon one of the guards of the field covered himself with a gray blanket and with his bow and arrows crept up to a concealed spot overlooking the field. From a distance the donkey saw the gray shape and thought, “Aha, a lady donkey.” And thinking this he made a cacophonous donkey bray and ran toward the fair object of his choice. When the guard heard the sound of the beast made he said, “Why it’s only a donkey!”, and with no trouble at all he crept up and killed it.
Thus I say: By keeping quiet even fools can become prosperous, but an ass, no matter how well-camouflaged, reveals himself as soon as he opens his mouth.