"“The wall will always be there to protect us,” they said. I later came to understand that it is merely a tangible, universally visible symbol of the far more important invisible walls separating the seventy-thousand subcommunities—or is it eighty-thousand now? One day, I firmly believe, there will be as many subcommunities as there are residents in the City."
January 1, 1970
https://en.wikiquote.org/wiki/Andrew_Fox_(author)