But in regard to painful emotions the reverse is true. The mind instinctively resists or flies from them, so that after a habit of suppressing such emotions is formed, until the susceptibility diminishes, and sometimes appears almost entirely destroyed. Thus a person often exposed to danger ceases to be troubled by fear, because he forms a habit of suppressing it. A person frequently in scenes of distress and suffering learns to suppress the emotions of painful sympathy. The surgeon is an example of the last case, where, by repeated operations, he has learned to suppress emotions until they seldom recur. A person inured to guilt gradually deadens the pangs of remorse, until the conscience becomes "seared as with a hot iron." Thus, also, with the emotion of shame. After a person has been repeatedly exposed to contempt, and feels that he is universally despised, he grows callous to any such emotions. The mode by which the mind succeeds in forming such a habit seems to be by that implanted principle which makes ideas that are most in consonance with the leading desire of the mind become vivid and distinct, while those that are less interesting fade away. Now no person desires to witness pain except from the hope of relieving it, unless it be that, in anger, the mind is sometimes gratified with the infliction of suffering. But, in ordinary cases, the sight of suffering is avoided except where relief can be administered. In such cases, the desire of administering relief becomes the leading one, so that the mind is turned off from the view of the suffering to dwell on conceptions of modes of relief. Thus the surgeon and physician gradually form such habits that the sight of pain and suffering lead the mind to conception of modes of relief, whereas a mind not thus interested dwells on the more painful ideas. The mind, also, can form a habit of inattention to our own bodily sufferings by becoming interested in other things, and thus painful sensations go unnoticed. Some persons will go for years with a chronic headache, and yet appear to enjoy nearly as much as those who never suffer from such a cause. Again: those who violate conscience seem to relieve themselves from suffering by forming a habit of dwelling on other themes, and of turning the mind entirely from those obligations which, when contemplated, would upbraid and pain them. Thus, too, the sense of shame is lost. A habit is formed of leading the mind from whatever pains it to dwell on more pleasurable contemplations.