[67] [cap.15] I have now therefore explained, in no superficial manner, in what way a husbandman differs from a tiller of the ground, and a shepherd from a keeper of sheep. There is also a third point, having some connection with what has already been said, which we will now proceed to speak of. For I consider that a horseman and a rider differ; meaning by this statement, not merely that one man who is carried on a neighing animal differs from another man who is carried on a similar beast, but the motion of the one is different from the motion of the other; therefore the man who gets on a horse without any skill in horsemanship, is correctly called a rider,