As long as the breath is in the body, the body is alive; and when the breath has left the body, the body becomes a useless thing. This shows us the importance of the breath. It reaches within to every part of the body. The hair has a little sensation in the root. If one hair is pulled we feel pain. The nail has a little feeling in it. If it is cut we feel it. But when the hair and nail are cut off they have no sensation. This shows us that the more any part of the body is connected with the breath the more sensation it has. Those parts that are most connected with the breath have the most feeling.