To sustain this inner calm will not be easy. Many a time, in test situations, he will fail. But even when the negative, explosive, or depressive emotion asserts itself strongly, he is not to show it in behaviour nor express it in speech. For this is a step towards that control of self, that impersonality, which is what the quest means. If mind influences body, body also influences mind. From the physical control he may proceed to the mental.
-- Notebooks Category 6: Emotions and Ethics > Chapter 3: Discipline Emotions > # 32