The object with which fasting is practiced by those who live in retirement is to let the breath pass through every vein and tube of the body, which can be made possible only when there is no foreign substance, such as food or even drink, in the body to block the channels. When the breath has touched every particle of the body, the body naturally becomes more sensitive and the pores of the skin open, making the centers transparent, so as to feel, outwardly and inwardly, all that is to be felt. This can be understood by seeing the difference between the intelligence and the intuitive faculty of a fine person and of a dense person.