I'd like one message to come across to all child-prodigies and precocious geniuses: You're not a "rare natural resource", "human capital" or any other such demeaning term. You're not responsible for solving ANY of the world's problems: you don't have to cure cancer or AIDS, you don't have to extinguish poverty, you don't have to solve the energy crisis. It's jut not your problem if you don't WANT it to be. Do what YOU ENJOY and LIKE, forget about other people's problems, forget even about the problems of your future selves! And do take advantage of you "special" or "celebrity" status, use it to get money and any unfair benefits you can get and waste them having fun. You're human beings and you are only supposed to live for your own enjoyment! If you enjoy helping others or solving the world's problems, do so. If not, fuck it all and just have fun!
Just to play devil's advocate here, most people actually do enjoy helping others. If you're the rare person that doesn't like helping other people at all, then it's probably a waste of my effort to try to make you. So "do what you like to do" != "be selfish" in all cases.
That's basically what it is, and maybe also a mindset of believing you matter as your own person, rather than just a means to and ends. Having at least some selfishness of that sort (at least when living in a culture designed for it - maybe things are different in more group-oriented cultures) is really important for things like being confident, being able to say no to others' requests, and not getting depressed.
Why wouldn't you advocate pure selfishness? Selfishness is a Good Thing. Why do we do anything? Because it satisfies some internal desire or drive. Selfishness is the epitome of living.