Emotional intelligence gives you a competitive edge. Even at Bell Labs, where everyone is smart, studies find that the most valued and productive engineers are those with the traits of emotional intelligence -- not necessarily the highest IQ. Having great intellectual abilities may make you a superb fiscal analyst or legal scholar, but a highly developed emotional intelligence will make you a candidate for CEO or a brilliant trial lawyer.
Empathy and other qualities of the heart make it more likely that your marriage will thrive. Lack of those abilities explains why people of high IQ can be such disastrous pilots of their personal lives.
An analysis of the personality traits that accompany high IQ in men who also lack these emotional competencies portrays, well, the stereotypical nerd: critical and condescending, inhibited and uncomfortable with sensuality, emotionally bland. By contrast, men with the traits that mark emotional intelligence are poised and outgoing, committed to people and causes, sympathetic and caring, with a rich but appropriate emotional life -- they're comfortable with themselves, others, and the social universe they live in.
A high IQ may get you into Mensa, but it won't make you a mensch.