Here is a short piece from the book.
To help the horse learn to understand what you want, you can make use of his nature. He is naturally curious and is apt to investigate things he hasn't seen or been around before. He is liable to run away from those same things. Thers's a spot somewhere in between (those tendencies) where an observing person can develop some skill at blending in thier plan for how they want the horse to manuever with the horse's willingness to do these things for a person. We can work with a horse this way because it's part of the horse's basic nature to want to get along. But the actual fact, as far as the horse is concerned, is that interaction with human beings is not natural. For a person to sit up there on his back is even less so. This is the reason we need to observe the horse and learn to feel of him and help him feel of us. To get the idea of feel, the horse handler needs to understand how the horse exists and survives in the world, which is through his senses. When it comes to cooperating with the human, we're talking about the feeling the horse has in every square inch of his hide and all through his mind, as it relates to a human touching him directly or in directly.
What are your thoughts on feel?
Do you have it?
Do you need it?
What happens when you don't/do have it?