If you are an effective manager of your self, your discipline comes from within; it is a function of your independent will. You are a disciple, a follower, of your own deep values and their source. And you have the will, the integrity, to subordinate your feelings, your impulses, your moods to those values.
Stephen R. Covey (1994). “Daily Reflections for Highly Effective People: Living THE SEVEN HABITS OF HIGHLY SUCCESSFUL PEOPLE Every Day”, p.111, Simon and Schuster
