You have to compete with others in the field. Sometimes the competition gets pretty fierce because you're competing for funds or grants to do your work, the financial work.

By the time I was in sixth grade I could bound every country in the world from memory.

To me, the noise of a threshing machine is better music than a lot of music I hear nowadays. I took a man's place in the threshing crew when I was only 14 years old.

A person that much interested in science is going to neglect his social life somewhat, but not completely, because that isn't healthy either. So one has to work it out according to one's own inclinations, how one wants to proportion these things.

The planets are never the same twice, they're always different, so they could compare the markings I had drawn with their current photographs and they knew that I was drawing what I was really seeing and it wasn't copied from somewhere.

I used to think about how nice it would be to visit the planets. Of course, I didn't expect to see in my lifetime what has happened. I knew it would happen some day, but it came along faster than I at first thought.

I was always looking ahead. I used to do all kinds of things for entertainment. When I was young, we had no radio, no TV. We were 30 miles from the public library, out in the sticks in Western Kansas, and so I'd do arithmetic exercises.