The Wolf and the Horse

A Wolf coming out of a field of oats met with a Horse, and thus addressed him: "I would advise you to go into that field. It is full of capital oats, which I have left untouched for you, as you are a friend the very sound of whose teeth it will be a pleasure to me to hear." The Horse replied: "If oats had been the food for wolves, you would never have indulged your ears at the cost of your belly."

Men of evil reputation, when they perform a good deed, fail to get credit for it.