A person seeking inner development must first of all make the attempt to give up certain formerly held inclinations. Then, new inclinations must be acquired by constantly holding the thought of such inclinations, virtues or characteristics in one’s mind. They must be so incorporated into one’s being that a person becomes enabled to alter his soul by his own will-power. This must be tried as objectively as a chemical might be tested in an experiment. A person who has never endeavored to change his soul, who has never made the initial decision to develop the qualities of endurance, steadfastness and calm logical thinking, or a person who has such decisions but has given up because he did not succeed in a week, a month, a year or a decade, will never conclude anything inwardly about these truths.