Every twenty minutes on the Appalachian Trail, Katz and I walked farther than the average American walks in a week. For 93 percent of all trips outside the home, for whatever distance or whatever purpose, Americans now get in a car. On average the total walking of an American these days - that's walking of all types: from car to office, from office to car, around the supermarket and shopping malls - adds up to 1.4 miles a week, barely 350 yards a day.

Deliberate cruelty to our defenceless and beautiful little cousins is surely one of the meanest and most detestable vices of which a human being can be guilty.

Sometimes I spend all day trying to count the leaves on a single tree... Of course I have to give up, but by then I'm half crazy with the wonder of it--the abundance of the leaves, the quietness of the branches, the hopelessness of my effort. And I am in that delicious and important place, roaring with laughter, full of earth-praise.

I thought of the wilderness we had left behind us, open to sea and sky, joyous in its plenitude and simplicity, perfect yet vulnerable, unaware of what is coming, defended by nothing, guarded by no one.

There's a lot of cruelty going on all the time, and I'm not just talking about inter-human cruelty. I'm talking about whole species becoming extinct, asteroids hitting planets, black holes gobbling up stars.

Our planet is blessed with vast natural treasures. If we use them wisely, beginning with the elimination of militarism and war, every human being will be able to live a healthy, prosperous existence.