Where change is perceptible, rapid change makes change itself even more visible. Velocity becomes a concrete condition, not just a measure of speed. Rapid change in cities has highly legible moments—the material reality of buildings, transport systems, re-placements of modest shops with luxury shops and of modes middle-classes with the rich professional class, a bike-path where there was none—and they can be both good and not so good. Further, when rapid transformation happens simultaneously in several cities with at least some comparable conditions, it also makes visible how diverse the spatial outcomes can be even when the underlying dynamics might be quite similar.

All of this brings to the fore the differing degrees of openness of cities. I prefer thinking of this as the incompleteness of cities, which means that they can constantly be remade, for better or for worse. It is this incompleteness that has allowed some of the world's great old cities to outlast kingdoms, empires, nation-states and powerful firms.

Let me take the imagery of incompleteness further. Powerful actors can remake cities in their image. But cities talk back. They do not take it sitting. Sometimes it may take decades, and sometimes it is immediate—see for instance the thousands of Stuttgart's residents who staged protests in August 2010 to stop the demolition of part of their old train station and the felling of hundreds of 200-year-old trees in the Schlossgarten to build a new high-speed transit hub. They succeeded. Yes, it is only part of the station and none of this is going to turn back the powerful forces of gentrification there. But it is a way in which the city can talk back.

We can think of the multiple ways in which the city talks back as a type of open-source urbanism: the city as partly made through a myriad of interventions and little changes from the ground up. Each of these multiple small interventions may not look like much, but together they give added meaning to the notion of the incompleteness of cities and that this incompleteness gives cities their long lives, thereby outlasting other more powerful entities.

In sharp contrast, I think that the model of "intelligent cities" as propounded by and the telepresence efforts of Cisco Systems misses this opportunity to urbanize the technologies they mobilize, and futilely seeks to eliminate incompleteness. The planners of intelligent cities, notably Songdo in South Korea actually make these technologies invisible, and hence put them in command rather than in dialogue with users. One effect is that intelligent cities represent closed systems, and that is a pity. It will cut their lives short. They will become obsolete sooner.

Beyond the imagery of open-source urbanisms, can we strengthen this positive scenario of the city's incompleteness by actually deploying open-source technologies in a variety of urban contexts?. Can we urbanize open-source technology?

As a technological practice of innovation, Open Source has not quite been about cities, but about the technology. Yet it resonates with what cities have and are at ground-level, where its users are. The park is made not only with the hardware of trees and ponds, but also with the software of people's practices. How can we forget the turnaround of New York's Riverside Park from being a no-go zone to being a park for all those who wanted to use it in part because dog-owners started to walk their dogs in large numbers. Having a dog was itself a function of feeling insecure in a city of high murder rates and much mugging. But the city allowed people to talk back: get a dog, walk your dog, go in groups, and you recover the territory of the park. The proliferation of farmers' markets was also not a top-down decision. It resulted from a mix of conditions, primarily the desire of city residents to have access to fresh produce. Here we see that a thousand individual decisions created a possibility for viable farmers markets.

There are many diverse initiatives that produce these kinds of "third space." With a very different aim, yet part of the same structural possibility, is the movement "Take Back the Night" initiated by women fighting to make streets safe from rape and sexual assault. As is that of women in Guatemala City who initiated a movement to take back the city," to reduce armed conflicts among the military, gangs, and criminals on the streets. What all of these examples share is that individuals can find a thousand ways of connecting to a network by initiating something, taking a step.

I find the opposite—the implications of the failure to urbanize—well captured in Eric Klinenberg's book Heat Wave that one of the reasons more than 700 people died in the very hot Chicago summer of 1995 was that they were afraid to leave their apartments because of the risks of murders and muggings outside. So they stayed in their apartments, and died of heat. How would urbanizing the actual technology of Open Source and its cognates affect these sorts of events whereby hundreds of people react to a condition in a similar way to produce perceptible civic outcomes: buying dogs/recovering the park, or wanting fresh produce/creating farmers' markets. And how can this open sourcing be used to better predict and avoid negative outcomes?

How can we urbanize the actual technology? In many ways, cities tend to urbanize technologies semi-autonomously, since it is still not quite feasible to simply plop down a new technology in urban space. It requires modifications, mediations. Major advances in building and other technologies have left a massive imprint on urban space. This is perhaps most visible in the sharp increases in density and networked systems that the new technologies have made possible.
But a closer look suggests that these modifications have to do with overcoming rigidities and risks, especially risks catalogued by insurance companies. This mode is then only vaguely one of urbanizing the technology.

Technologists, urbanists and artists are beginning to "urbanize" technology (see the Network Architecture Lab at Columbia, the SENSEable City Lab at MIT, and much of the work gathered at the Design and the Elastic Mind exhibit at MoMA). When this happens, the city becomes a heuristic space: it talks to the average resident or passer-by, it can make the most advanced applied technologies that can be used in cities visible. The city also makes visible the diversity of spatial forms through which these technological applications work, becoming legible even to the passer-by. I have long thought that all the major infrastructures, from sewage to electricity and broadband, should be covered by transparent walls and floors, so if you are waiting for the bus, you can actually see how the city all works and begin to get engaged. Today, when walls are pregnant with softwared capabilities, why not make this transparent? All our computerized systems should become transparent. It creates its own public shared domain.

Yet Open Source is different from those technologies and technological applications. I see in Open Source a DNA that resonates strongly with how people make the city theirs or urbanize what might be an individual initiative. And yet, it stays so far away from the city. I think that it will require making. We need to push this urbanizing of technologies to strengthen horizontal practices and initiatives. Leading urban civic institutions tend to verticalize this work of making the urban. But they do matter. Here the appropriate technology is more akin to developing an urban Wikileaks—vertical institutions that begin to leak and thereby enable citizens to work with at least some of what is useful in those leaks in the ways they see fit. This is akin to horizontalizing what is now vertical, imposed by top-down authority.

There is much work to be done. Recovering the incompleteness of cities means recovering a space where the work of open sourcing the urban can thrive. Developing an urban Wikileaks would take cities in a very different direction from the intelligent city model—and for the better.

Saskia Sassen is the Robert S. Lynd Professor of Sociology and Co-directs the Committee on Global Thought, Columbia University. She has written for the Guardian, the New York Times, Le Monde, and Newsweek International, among others, and contributes regularly to OpenDemocracy.net and Huffington Post. Her newest books include Territory, Authority, Rights: From Medieval to Global Assemblages (Princeton University Press, 2008) and A Sociology of Globalization (W.W. Norton, 2007).

Reprinted from the New City Reader #15: Local