There is nothing quite so gentle, deep, and irrational as running--and nothing quite so savage, so wild.

Barry L. Jacobs and colleagues from the neuroscience program at Princeton University showed that when mice ran every day on an exercise wheel, they developed more brain cells and they learned faster than sedentary controls. I believe in mice.

I do not yet want to form a hypothesis to test, because as soon as you make a hypothesis, you become prejudiced. Your mind slides into a groove, and once it is in that groove, has difficulty noticing anything outside of it. During this time, my sense must be sharp that is the main thing - to be sharp, yet open.

Deep down we are all still runners

Conditions are seldom ideal, and if one waits long enough for ideal conditions one is just making excuses.

Movement is the essence of life.

For those that endure until spring, existence is reduced to its elegant essentials.

The very idea of managing a forest in the first place is oxymoronic, because a forest is an ecosystem that is by definition self-managing.