It's a deep and all but certain truth about narcissistic personalities that to meet them is to love them, but to know them well is to find them unbearable. Confidence quickly curdles into arrogance; smarts turn to smugness, charm turns to smarm.
Narcissism, like the other personality disorders, is a condition that's known as ego-syntonic. In other words, the paranoid person really does believe that people are after him, and the narcissist really does believe that he or she is better than or more entitled than other people, and truly doesn't see why that's not the case.
Identical twins are ideal lab specimens for studying the difference between learned and inherited traits since they come from the womb preloaded with matching genetic operating systems. Any meaningful differences in their behaviors or personalities are thus likely to have been acquired, not innate.
