I challenged things that needed to be challenged at Purdue.

I made lots of talks and challenged lots of people.

I challenged things that needed to be challenged at Purdue.

But you've got to make choices, and you're not going to be right all the time.

Teaching was the most pleasant thing I did.

I was a stubborn cuss, and I made some mistakes.

Nixon was kind of a loner, he had a cold personality.