Whether they learn it from their family, school, or athletics, many people establish an identity by comparing themselves with others. When they see others gain power, information, money, or recognition, for instance, they experience what the psychologist Abraham Maslow called a feeling of deficiencya sense that something is being taken from them. That makes it hard for them to be genuinely happy about the success of otherseven of their loved ones.

HBR's 10 Must Reads on Managing Yourself by Harvard Business School Press