I still need to read Outliers, and now Nudge, not to mention a few other books.
However, is genius nature vs nuture? Perhaps is genius more an expression of potential, rather than raw intelligence? Its hard to argue against an initial value problem here. If you start out with a high IQ, and do the hard work, master your creative abilities, and harness both your IQ and hard work then you too can be a genius.
But is a high IQ necessary? and is hard work sufficient?
I am sure there is work out there that shows that people gifted musically have brains wired differently. Structurally identical. Just the individual connections would be more focused and/or more active during the displays of genius. We already know the brain responds to repetition - learning. So it shouldn't be surprising that genius involves hard work and problem solving in creative ways. Probably even in discrete jumps - rapid learning in short intervals.
The brain also acts via chemicals to suppress certain responses when it is concentrating. Just like people who shoot at targets. A shaking hand goes absolutely still as the brain zones in, focusing only on the one action - the release of the arrow, for example. The same should apply for rapid learning ... the kind of learning where breakthroughs happen. Einstein was self taught in mathematics. His genius was derived from at least some hardwork, experience, even maturity, and clarity of purpose. His clarity of purpose is best illustrated in his lack of ability to have a meaningful relationship with his wife and children ... he was too focused on his work.
So genetics, environment, IQ, and experience all play a role ... and I'll bet each genius has a unique distribution of those 4 qualities. So given that you dont control any of these, you might as well work hard - the benefits are obvious. Failing to be a genius, you just might make yourself (and the people around you) smarter.
Perhaps the one quality all geniuses have ... a good challenge. Something that compelled them to work hard, stay focused and motivated, and acheive.