I got Mr. Ed, the talking TV horse, mixed up with Francis the Talking Mule from the movies, he later said. I meant to say `mule,' because a mule is not a thoroughbred. A jackass is a thoroughbred, but a mule is a cross, I think, between a jackass and a horse. I think a mule is worse than a jackass.Billy Tubbs calls Norm Stewart a mule, denounces cross-breeding, as quoted in Vahe Gregorian's OU-MU game writeup. Those were the days indeed.