Approximately 26.5 million work animals, of which 5.5 million were mules, stocked our pastures and stables in 1920. Total mules in Missouri approached one-half million, but Texas led all states with 1.1 million head. The 68,457 mule colts reported in Missouri that year exceed any other states' number by 25 percent. They are tolerant of heat, seldom founder, live long, enjoy better health, are more sure-footed, have harder hooves, seldom fight each other seriously, and are considerably more intelligent than horses. Some persons in the work stock era would not own or use mules.
Mules are strong-willed animals.
They know exactly what they want and are willing to pay a price to get it. More skills are required to handle mules than horses, but the rewards are greater. Not really, but they are cautious. From the mule's point of view those activities in which we humans ask it to engage may be unfamiliar to its past experiences, contrary to his nature, or downright unreasonable in the amount of pain or trauma inflicted on it. When it refuses to comply, regardless of the unreasonableness of our request, we call it stubborn even though it is using good judgement.