Times of doubt and uncertainty lead many people turn to self-help books in search of encouragement, guidance and self-affirmation. The positive self-statements suggested in these books, such as "I am a lovable person" or "I will succeed," are designed to lift a person's low self-esteem and push them into positive action. According to a recent study in Psychological Science, a journal of the Association for Psychological Science, however, these statements can actually have the opposite effect.