The words of the social critic Eric Hoffer were ringing true: "Every great cause begins as a movement, becomes a business, and turns into a racket."

We run when we're scared, we run when we're ecstatic, we run away from our problems and run around for a good time.

Know why people run marathons? …Because running is rooted in our collective imagination, and our imagination is rooted in running. Language, art, science; space shuttles, Starry Night, intravascular surgery; they all had their roots in our ability to run. Running was the superpower that made us human — which means its a superpower all humans posses.

In 'Tarahumara' land, there was no crime, war or theft. There was no corruption, obesity, drug addiction, greed, wife-beating, child abuse, heart disease, high blood pressure, or carbon emissions. They didn't get diabetes, or depressed, or even old: 50-year-olds outran teenagers.

When it comes to mentors, you can't beat survival.

it’s easy to get outside yourself when you’re thinking about someone else.

We've created an unnatural form of running. It's not just the shoes, but we run on artificial surfaces - straight ahead, hard and steady - instead of speeding up and slowing down, reacting to the terrain with changes of pace and rhythm.