Duke University did a study on "peace of mind." Factors found to contribute greatly to emotional and mental stability are:

• The absence of suspicion and resentment. Nursing a grudge was a major factor in unhappiness.
• Not living in the past. An unwholesome preoccupation with old mistakes and failures leads to depression.
• Not wasting time and energy fighting conditions you cannot change. Cooperate with life, instead of trying to run away from it.
• Force yourself to stay involved with the living world. Resist the temptation to withdraw and become reclusive during periods of emotional stress.
• Refuse to indulge in self-pity when life hands you a raw deal. Accept the fact that nobody gets through life without some sorrow and misfortune.
• Cultivate the old-fashioned virtues--love, humor, compassion and loyalty.
• Do not expect too much of yourself. When there is too wide a gap between self-expectation and your ability to meet the goals you have set, feelings of inadequacy are inevitable.
• Find something bigger than yourself to believe in. Self-centered egotistical people score lowest in any test for measuring happiness.