But if you teach the horse to go with a slack bridle, to hold his neck up and to arch it towards the head, you will cause the horse to do the very things in which he himself delights and takes the greatest pleasure. A proof that he delights in them is that whenever he himself chooses to show off before horses, and especially before mares, he raises his neck highest and arches his head most, looking fierce; he lifts his legs freely off the ground and tosses his tail up.