Editor's Note: The following is an excerpt from Triumph Of The City by Edward Glaeser. Published by arrangement with The Penguin Press, a member of Penguin Group (USA), Copyright  (c) 2011 Edward Glaeser.

Two hundred forty-three million Americans crowd together in the 3 percent of the country that is urban. Thirty-six million people live in and around Tokyo, the most productive metropolitan area in the world. Twelve million people reside in central Mumbai, and Shanghai is almost as large. On a planet with vast amounts of space (all of humanity could fit in Texas—each of us with a personal townhouse), we choose cities. Although it has become cheaper to travel long distances, or to telecommute from the Ozarks to Azerbaijan, more and more people are clustering closer and closer together in large metropolitan areas. Five million more people every month live in the cities of the developing world, and in 2011, more than half the world’s population is urban.

Cities, the dense agglomerations that dot the globe, have been engines of innovation since Plato and Socrates bickered in an Athenian marketplace. The streets of Florence gave us the Renaissance, and the streets of Birmingham gave us the Industrial Revolution. The great prosperity of contemporary London and Bangalore and Tokyo comes from their ability to produce new thinking. Wandering these cities—whether down cobblestone sidewalks or grid-cutting cross streets, around roundabouts or under freeways—is to study nothing less than human progress.

In the richer countries of the West, cities have survived the tumultuous end of the industrial age and are now wealthier, healthier, and more alluring than ever. In the world’s poorer places, cities are expanding enormously because urban density provides the clearest path from poverty to prosperity. Despite the technological breakthroughs that have caused the death of distance, it turns out that the world isn’t flat; it’s paved.

The city has triumphed. But as many of us know from personal experience, sometimes city roads are paved to hell. The city may win, but too often its citizens seem to lose. Every urban childhood is shaped by an onrush of extraordinary people and experiences—some delicious, like the sense of power that comes from a preteen’s first subway trip alone; some less so, like a first exposure to urban gunfire (an unforgettable part of my childhood education in New York City thirty-five years ago). For every Fifth Avenue, there’s a Mumbai slum; for every Sorbonne, there’s a D.C. high school guarded by metal detectors.

Indeed, for many Americans, the latter half of the twentieth century—the end of the industrial age—was an education not in urban splendor but in urban squalor. How well we learn from the lessons our cities teach us will determine whether our urban species will flourish in what can be a new golden age of the city.

My passion for the urban world began with the New York of Ed Koch, Thurman Munson, and Leonard Bernstein. Inspired by my metropolitan childhood, I’ve spent my life trying to understand cities. That quest has been rooted in economic theory and data, but it has also meandered through the streets of Moscow and São Paulo and Mumbai, through the histories of bustling metropolises and the everyday stories of those who live and work in them.

I find studying cities so engrossing because they pose fascinating, important, and often troubling questions. Why do the richest and poorest people in the world so often live cheek by jowl? How do once-mighty cities fall into disrepair? Why do some stage dramatic comebacks? Why do so many artistic movements arise so quickly in particular cities at particular moments? Why do so many smart people enact so many foolish urban policies?

2 Comments

1. 1. bucketofsquid 09:24 AM 8/19/11

   Cities are a great idea. They let pathogens spread much faster and infect far more people. They also allow enemies to have a much easier time causing catastrophic damage.

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2. 2. Worffy 01:02 PM 8/19/11

   Cities are the heart of civilization. Since so many Americans HATE their own cities and rush to live in wilderness areas and small towns I wonder....does it mean that Americans are perhaps less civilized than many other people?

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