I find this very inspiring, because it seems like he's not necessarily a genius but just worked really hard and didn't give up. Also, he was in his late fifties when he published his proof, going against the commonly held belief that mathematicians do their best work before 40.

[edit:] Peter Sarnak from Princeton does call him a genius. When you read about him online, you actually find several other people who have known/worked with him to call him that as well. So I guess I was wrong.

> Why did you solve this problem and not somebody else?

> I think the important reason is that I persisted for several years. I didn’t give up.

> How long did you work on your conjecture?

> I worked on my conjecture for four years. I worked on it seven days a week. I didn’t take any breaks almost. If we count the time I spent thinking about the problem, then it was more than 10 hours a day. If you count sitting in front of a desk or using a computer, then it was five or six hours a day.