For no person can alter or improve his horse's mouth beyond the capacity of his own Hand. Hence, if your Hand is bad, you can never make your horse's mouth good; and if your horse's mouth is good you will soon reduce it to a level with your Hand
~ John Adams
Briefly, all training is this and nothing more: the legs to provoke action; the hands to direct it.
~ E. Beudant
So, to be masters of our horses, we must be masters of ourselves.