QUOTE : In unfamiliar terrain, a plastic bag impaled on barbed wire is snapping in the breeze. Mules are skittish about that because they haven’t seen it before, and it reminds them of a predator. So the “muleteer” beats them there too. Eventually, when the mules tire of getting beaten, or are just fed up dealing with a less intelligent species, they use the tremendous power of their hind legs to kick out the tug chains and run away. For this, mules are known as “ornery.” In English we use the common phrase “stubborn as a mule,” a classic example of man ascribing stupidity to the beast instead of to himself.