There are three stages in scientific discovery. First, people deny that it is true, then they deny that it is important; finally they credit the wrong person.

Hunters will tell you that a moose is a wily and ferocious forest creature. Nonsense. A moose is a cow drawn by a three-year-old.

Consider the Lichen. Lichens are just about the hardiest visible organisms on Earth, but the least ambitious.

I don't want to go and start trying to make jokes in places like India, Tanzania or Iraq. Afghanistan is not a funny place.

To me, the greatest invention of my lifetime is the laptop computer and the fact that I can be working on a book and be in an airport lounge, in a hotel room, and continue working; I fire up my laptop, and I'm in exactly the same place I was when I left home - that, to me, is a miracle.

A sign in the yard of a church next door said CHRIST IS THE ANSWER. (The question, of course, is: What do you say when you strike your thumb with a hammer?)

I wanted to quit and to do this forever, sleep in a bed and in a tent, see what was over the next hill and never see a hill again. All of this all at once, every moment, on the trail or off.