No doubt the way of self-discipline is a very difficult way. It is the way of mastery, of power; but it is a hard and difficult path. Practicing discipline by sitting in a certain pose or posture is very difficult to keep up for a long time. If one makes a vow to refrain from eating fruit, sweet or sour things, a vow of silence, of fasting, of standing so many hours, or walking, or staying up for part of the night or the whole night, it is not always easy to keep to it. Self-discipline is learned by going against one's own inclinations. Why should one go against them? Are inclinations not natural? One cannot say what is one's own inclination; all inclinations are borrowed here, and what one calls natural is what one has become accustomed to.