As a species we appear to be uniquely placed to exploit the benefits of working together. Our greatest talent is the ability to learn from each other, and we learn more deeply and thoroughly when we’re face-to-face. There is little that you own or use or know that wasn’t created by someone else. Humans are an intensely social species that excels in producing things together. Just as ant colonies do things that are far beyond the abilities of isolated insects, when humans come together we achieve much more than we ever could in isolation.
Critical to this success is our ability to create functioning cities. It is the proximity that they provide that makes it easier to exchange goods and ideas. The spread of knowledge from engineer to engineer, from designer to designer, from trader to trader is the same as the flight of ideas from painter to painter, and urban density has long been at the heart of that process. Cities make it easier to watch and listen and learn.
Cities enable the collaboration that makes humanity shine most brightly. Because humans learn so much from other humans, we learn more when there are more people around us. Urban density creates a constant flow of new information that comes from observing others’ successes and failures.
For this reason cities are unparalleled as melting pots for new ideas, centres for trade and commerce, seats of learning and the focus for discovery. They are at the cutting edge of whatever mankind chooses to put its collective mind to.
Since Plato and Socrates debated in an Athenian marketplace cities have been engines of innovation. The streets of Florence gave us the Renaissance. The streets of Birmingham gave us the Industrial Revolution. The great prosperity of contemporary London, Bangalore and Tokyo comes from their ability to produce new thinking. Cities speed innovation by connecting their smart inhabitants to each other. To thrive, cities must attract smart people and enable them to work collaboratively.
Athens flourished because of small random events that then multiplied through urban interaction. One smart person met another and sparked a new idea. That idea inspired someone else, and all of a sudden something really important had occurred. The ultimate cause of Athens success may seem mysterious, but the process is clear. Ideas move from person to person within dense urban spaces, and this exchange occasionally creates great leaps in human creativity.
It is no exaggeration to say that our cultures, our prosperity, and our freedom are all ultimately gifts of people living, working, and thinking together in cities. For this reason I believe that our capacity to foster functioning cities is mankind’s most important achievement.
Even new technologies, from the book to Google, have failed to challenge our fundamentally social nature. They’ve made it easier to learn without meeting face-to-face, but that hasn’t eliminated the extra edge that comes from interacting in person. Since new technologies have increased the returns from new ideas, they have also increased the returns from face-to-face collaboration.
Because ideas flow readily from person to person in the dense corridors of cities like Bangalore or London, people are willing to overcome the problems that the necessary density creates. At some point in their history all of the world’s cities have suffered the great scourges of urban life; disease, crime, congestion. We go to great lengths to provide clean water and sanitation, safe streets and elaborate transport networks because the benefits of density are so substantial. In London for example the elaborate sewage systems of Joseph Bazalgette helped to reduce the incidents of cholera epidemics, while the construction of the London Underground network moves around 3.5M people every day.
On average, as the share of a country’s population that is urban rises by 10 percent, the country’s per capita output increases by 30 percent. Per capita incomes are almost four times higher in those countries where a majority of people live in cities than in those countries where a majority of people live in rural areas. In fact Americans who live in metropolitan areas with more than a million residents are, on average, more than 50 percent more productive than Americans who live in smaller metropolitan areas.
This efficiency and the prosperity that it can lead to is why 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 became urban.
Nowhere does this proximity pay greater dividends than in a city’s streets and other public spaces, where physical connection is at its most transparent and egalitarian. Cities pull people out of private space into public areas which helps make them centres for connection, competition, collaboration and of new ideas. As the stage for public life, great streets and spaces are also essential for developing social cohesion, endowing a sense of identity, maintaining a well functioning democracy, creating social equality, providing space for community life, moving people and goods, and promoting healthy lifestyles.
At the same time transportation has always determined urban form. In walking cities like central Florence or Jerusalem’s old city, the streets are narrow, winding, and crammed with shops. When people had to use their legs to get around, they tried to get as close as possible to each other and to the waterways that provided the fastest way in and out of the city. Areas built around trains and elevators, like midtown Manhattan and the Chicago Loop, have wider streets often organised in a grid. There are still shops on the streets, but much of the office space is much further from the ground. Cities built around the car, like much of Los Angeles and Phoenix and Houston, have enormous, gently curving roads and often lack sidewalks. In those places, shops and pedestrians retreat from the streets into malls.
The power of transportation to shape cities is, again, most acute within its streets and other public spaces. In fact the desire for expedient movement is very often in conflict with the desire for proximity.
So the layout of our cities is defined by the way we travel, while the success of our cities is governed by their ability to connect people through proximity. And nowhere are these two issues more obvious or more important than in a city’s streets. Therefore it becomes critical that those responsible for the design of a city’s streets have the ability and desire to find the optimum balance of these two competing demands. And their successful design can only be achieved through the fullest understanding of the complex and delicately balanced workings of cities.
With this in mind, finding an answer to the following question has, in my mind, become the Holy Grail of urban street design and critical to the success of our cities...
“How can we design urban streets that will encourage all of the things that we value; promoting healthy, active lifestyles, reducing pollution, helping to develop social cohesion, contributing towards a places sense of identity, providing equality of opportunity and providing space for community life, whilst at the same time providing the conditions for human endeavour to thrive and moving people and goods around efficiently and safely?”
Quite simply, great cities are made up of great streets and their successful design is in everyone’s interest.