As production becomes increasingly clean and knowledge-based, as our urban economies tip dramatically to service industries, as racism and ethnic animosities ebb, and as the model of mixed use becomes more and more persuasive and visible, cities are in a position to dramatically rethink zoning as a medium for leveraging and usefully complicating difference, rather than simply isolating it.
The biographer of Robert Moses, Robert A. Caro, refers to the bridges and underpasses of the famed New York State parkways. These bridges and underpasses are quite low, intentionally specified by Moses to allow only private cars to pass. All those who traveled by bus because they were poor or black or both were barred from the use and enjoyment of the parkland and its "public amenities" by the technical design of the bridges. Even at the time of Robert Moses, a political statement of the form "We don't want them blacks in our parks" would have been unacceptable in New York State. But a technological expression of the same prejudice appeared to be all right. Of course, to the public the intent of the design became evident only after it was executed, and then the bridges were there.
Lying somewhere between a club and a loosely defined set of friends, the SMALL GROUP is a repeated theme in the lives of the successful. Benjamin Franklin had the Junto Club, Tolkien and C.S. Lewis had The Inklings, Jobs and Wozniak had Homebrew.
Around a dozen members is the sweet spot of social motivation: small enough to know everyone, yet large enough that the group won’t collapse if one or two members’ enthusiasm wanes; small enough that you are not daunted by competing with the whole world, yet large enough that you still need to be on your toes to keep up.