This 10,000 hours of practice seems to line up with someone doing a PhD in 4 years on ~7 hours a day of work. I've met many people with PhDs that I would consid

This 10,000 hours of practice seems to line up with someone doing a PhD in 4 years on ~7 hours a day of work. I've met many people with PhDs that I would consider morons, so I think you could argue that you can be successful with only practice for some definitions of success. However, I think you're unlikely to put yourself through something like 4-5 years of constant work if you don't have some other qualities. (i.e. It's gotta be a combination of innate qualities and practice)