I haven't personally read it, but it's been referenced by enough other authors that I know it well, so I recommend reading Mindset by Carol Dweck. Basically she found there are two ways to look at ability: innate and learned. People who think they improve through growth outperform those who think their abilities are set in stone.

I used to think I was naturally gifted in some areas and weak in other areas, but in reality I was just passionate and spent many hours of my childhood learning skills and a way of thinking about the world that made me excel in certain disciplines. Sure there are outlier geniuses, athletes, etc, but when it comes to learning and brain capacity I believe most people have similar potential.