I was looking at ageing in action, in black-and-white MRI pixels, death and dissolution foretold, and already partly achieved. My 70-year-old brain was shrunken and withered, a worn and sad version of what it once must have been. There were also ominous white spots in the white matter, signs of ischaemic damage, small-vessel disease, known in the trade as white matter hyperintensities – there are various names for them. They looked like some evil pox. Not to put too fine a point on it, my brain is starting to rot. I am starting to rot. It is the writing on the wall, a deadline.

I’ve been very fortunate in that respect. In the early days I liked to be the bomb of the expedition, and rush on ahead and do things faster than anybody else. Those days merged very pleasantly into periods when I organized and inspired expeditions and selected these younger people who were then the bombs of the operation. And then it drifted into this involvement with the people of the area, still loving the mountains, but finding the people just as important too. And on and on it’s gone. As I get older and less physically capable, I find other challenges have grown up and become just as important to me.

Pain and loneliness.

Losing my mind.

Abraham Lincoln truly inspired me. It wasn't just the freeing of the slaves, he kept the Union together. Some people even forget that today. What I think inspired me was the fact that in spite of being the president of the United States he retained a certain down-to-earth quality. He never got to be a big shot, and he cared about people.

It's family, and it's faith, and it's friends. I would tell them that. Don't forget that. In your brilliance, don't turn your back on your friends. Don't think you're entitled to something because you're smarter than the next guy.

It’s family, and it’s faith, and it’s friends, and it’s not the glamour of the Presidency, or the wonder of going to receive the Nobel Prize. All those are important, of course. But maybe it’s just that I’m 71 years old now. It’s family, and it’s faith, and it’s friends.

If you really want to make a difference, whether it’s in helping other people, or whether it’s in fighting for your country, or whether it’s in the political arena, or journalism, or physics, you’ve got to persevere. You’ve got to understand that there are going to be some enormous bumps in the road.

When I lost a race for the United States Senate, I thought the world was going to end for me politically, and 18 years later I was elected President of the United States. The biggest disappointment was that I wasn't able to communicate properly to the American people — with the proper conviction and the proper ability — where the country really stood. The pessimists, the naysayers, the change-wanters overwhelmed me, and I wasn't good enough. I wasn't articulate enough to have the country understand that we weren't in a recession, that we were in a rather booming economy in the last half of my presidency. That was a personal shortcoming, a failure on my path.

One of the historians here in Williamsburg talked about War and Peace. I had to read that in school. It was an inspiring, lengthy treatise. I read it twice. It taught me a lot about life. There was a marvelous book by Salinger called Catcher in the Rye. There was a book about discrimination called Gentleman's Agreement. These books I think helped shape my life. But to be honest with you, not one book stands out as the defining book for me.