As we live and as we are, Simplicity - with a capital S - is difficult to comprehend nowadays. We are no longer truly simple. We no longer live in simple terms or places. Life is a more complex struggle now. It is now valiant to be simple: a courageous thing to even want to be simple. It is a spiritual thing to comprehend what simplicity means.
Walkers are 'practitioners of the city,' for the city is made to be walked. A city is a language, a repository of possibilities, and walking is the act of speaking that language, of selecting from those possibilities. Just as language limits what can be said, architecture limits where one can walk, but the walker invents other ways to go.