The Importance Of Physical Space

David Brooks had an excellent column the other day on the "splendor of cities," how these massive agglomerations of people remain essential even in the age of Facebook, Facetime, Twitter and email. While many people predicted during the frenzy of the dot-com bubble that the rise of the internet would mean the "end of geography" - the zeroes and ones hurtling across the fiber optic cables should supply us with all the interactions we need - that hasn't happened. Instead, cities have become more important than ever. Here's Brooks:

This is a point Edward Glaeser fleshes out in his terrific new book, “Triumph of the City.” Glaeser points out that far from withering in the age of instant global information flows, cities have only become more important.

That’s because humans communicate best when they are physically brought together. Two University of Michigan researchers brought groups of people together face to face and asked them to play a difficult cooperation game. Then they organized other groups and had them communicate electronically. The face-to-face groups thrived. The electronic groups fractured and struggled.

Cities magnify people’s strengths, Glaeser argues, because ideas spread more easily in dense environments. If you want to compete in a global marketplace it really helps to be near a downtown. Companies that are near the geographic center of their industry are more productive. Year by year, workers in cities see their wages grow faster than workers outside of cities because their skills grow faster. Inventors disproportionately cite ideas from others who live physically close to them.

For years, cities like Detroit built fancy towers and development projects in the hopes that this would revive the downtown core. But cities thrive because they host quality conversations, not because they have new buildings and convention centers.

The cities that have thrived over the past few decades tend to have high median temperatures in January (people like warm winters and other amenities). But even cold cities like Chicago can thrive if they attract college grads. As the number of college graduates in a metropolitan area increases by 10 percent, individuals’ earnings increase by 7.7. This applies even to the high school grads in the city because their productivity rises, too.

Somewhere, Jane Jacobs is smiling. As I noted in a recent Times Magazine article, the physicists Geoffrey West and Luis Bettencourt have tried to quantify the productivity gains produced by cities. They began by data mining vast tracts of statistics released by various government agencies:

According to the data, whenever a city doubles in size, every measure of economic activity, from construction spending to the amount of bank deposits,increases by approximately 15 percent per capita. It doesn’t matter how big the city is; the law remains the same. “This remarkable equation is why people move to the big city,” West says. “Because you can take the same person, and if you just move them to a city that’s twice as big, then all of a sudden they’ll do 15 percent more of everything that we can measure.” While Jacobs could only speculate on the value of our urban interactions, West insists that he has found a way to “scientifically confirm” her conjectures. “One of my favorite compliments is when people come up to me and say, ‘You have done what Jane Jacobs would have done, if only she could do mathematics,’ ” West says. “What the data clearly shows, and what she was clever enough to anticipate, is that when people come together, they become much more productive.”

At this point, the science remains mostly statistical - I don't think anyone has a clear idea why density produces innovation, or why people who are physically close are so much more productive. As a result, we end up relying on vague words like "knowledge spillovers" or "knowledge trading" or "implicitly exchanged information." Nevertheless, the statistics are convincing. Consider a study published earlier this year by Isaac Kohane, a researcher at Harvard Medical School. Kohane’s question was simple: How does physical proximity affect the quality of scientific research? To answer this question, he analyzed more than 35,000 different peer-reviewed papers, mapping the precise location of every single co-author. Once the data was amassed, the correlation became clear: When co-authors were located closer together, their papers tended to be of significantly higher quality, at least as measured by the number of subsequent citations. The best research was consistently produced when scientists were working within ten meters of each other, while the worst papers tended to emerge from collaborators located a kilometer or more apart. (On average, a paper with four or fewer authors located in the same building was cited 45 percent more than if the authors were in different buildings.) For whatever reason, electronic interactions are not (at least not yet) a substitute for the real world; Facetime can't compete with a real face. As the work of Glaeser and Kohane demonstrates, our most important new ideas typically don’t arrive on a screen. Rather, they emerge from idle conversation, from too many people sharing the same space.