You have to learn the opponent psychologically inside out and mental strength is one of the important makers. You're either gonna break it or make it.

When you're successful for so many years, the scariest part is that you're getting too comfortable because you've had so much success.

I learned in my Ph.D. the discipline I needed to be successful. Most boxers are not that disciplined. They have talent, but the self-organization - the ability to schedule yourself and your priorities - is lacking. My studies were about the control of training on both the psychological and the physical side.

In Soviet times the border was closed so we couldn't get out of the country, and I had been reading Robinson Crusoe. I wanted to see the ocean, I wanted to see boats, I wanted to see black people, because we didn't have that in the Soviet Union. I was all excited by that stuff.

It's such a gift in my life to be able to compete - to have the health.

In the old days, when Muhammad Ali was fighting Ken Norton, Joe Frazier and George Foreman, there was a lot of excitement in the heavyweight division, I have to admit it.

Politics is comparable to boxing. The only thing is that in politics there are basically no rules. In boxing, you can get a black eye, but in politics you can get poison in your food or a bullet in the head. It's definitely rougher and tougher than other sports.