ty what the vital signs are to a living organism: the condition of life. Any major perturbation can bring irreparable damage; moreover, they are performed subconsciously. No one questions the speed of an escalator, the train-stops´ frequency , the flow of a crowd, the silence of a Sunday-morning, the smells of a covered passage or the sound of fireworks at New Year´s Eve. Even insanity has to compel: the fools wandering through trains and buses, babbling and gesticulating violently, acting as if they would jump through the window at any moment, wait for the stopping signal, push the right button when it lights, then disappear in the crowd. At night, after the most boring week-day, after retiring in the privacy of a home in the most ordinary of streets, speeding cars following the slow pace of traffic lights still send a faint signal, like a snore that reminds you that this giant that you help generate with every breathing moment is still alive.

The logic of a city´s everyday life becomes the reality of each creature who´s emerged in it. For visitors and residents alike, the labyrinth of streets walked by strangers minding their own business as if under a spell, with a parallel world emerging at every corner, seems to go on forever. Everything functions unperturbed up to the edge of the void. But once you get there, it takes only one step to annul every rule that created the universe on the other side.

Berlin Tempelhof Airport, Berlin, Germany, - opened: 1923; - closed: 2008; - current state: open to the public during daytime; events

The colors of the Tempelhoferfeld and its enormous sky seem frozen in a nostalgic picture of a past golden-age. There are no shadows. You can feel the wind and, in some places, see it bending the over-grown grass. People seem to float. Spread through this field conceived for the scheduled take-off and landing of airplanes, every human movement loses its rhythm with the distance and fades into a slow, continuous slide. There are asphalt runways which, at first, you might feel inclined to follow. But after a few steps, you suddenly realize that there´s no point in walking a straight line through this even surface, you can follow any direction, or, better yet, no direction at all. As you advance through the field, the sounds, smells and colors of the city fade away.

Events are sometimes organized in Tempelhof. This summer, the exhibition “ The World is not Fair – Die große Weltausstellung 2012” (The big World Exhibition 2012) spread a few city particles across this void. Searching for the location of a performance, I faintly heard some music dissipated by the wind. It took me a moment to find the source: a small, wooden pavilion. With nothing else around except grass and asphalt, I could walk directly to it. Inside, the music screamed and, strangely, people looked like people again, not like the ghosts on the outside. I could grasp their dance movements, hear their conversations and follow their gaze. Everything that happened INSIDE the shack made sense: the music had rhythm, the performance had a structure, there was a beginning and an end to everything and a purpose in people attending this. The INSIDE belonged to the city. On the OUTSIDE however, everybody leaving the enclosure and dissipating in all directions became ghosts again, they started sliding instead of walking, while the music faded and the sky became gigantic again until, together with the grass, it was the only thing left. Nothing duller and nothing more beautiful. When the sound of passing cars became distinguishable again, it seemed more obvious than in the middle of a boulevard. The void had made it clear that this constant background of city life is not part of the ´real´ but only an occurrence.

Tempelhof is the ultimate void. Detached from both city and nature, its laws are undetermined. Managed as it is right now, serving no particular purpose and being constantly maintained in order to keep nature from taking it over, it looks just like a trace of sulfuric acid, dropped by a malicious God on the city in order to dissolve it and suspend its laws. This huge temporarily purposeless field is full of questions and possibilities. Behaviors are easy to observe here, but hard to control and even harder to put to use. As long as it stays that way, eluding clear definitions, Tempelhof will remain “the void”, an entity contesting “the city”. This is a more powerful reason than the financial one to try to control (through fencing, guarding or closing after dark) maintain (through cleaning, mowing, repairing the asphalt) and to define this place.

The simple act of opening it to the public, with slogans like “Spass an die Leere” (Fun with the Void) or “Tempelhofer Freiheit” (Tempelhof freedom) (http://www.tempelhoferfreiheit.de), along with a “manual” of proposed activities, is a first try of “taming” the void. The people and uses that animate this abandoned airport are a projection of its future. The field could easily remain construction-free, but the goal of the numerous projects that were suggested for this site strive to define functional areas, schedules, constructable and non-constructable areas, people and activities flows, etc.
Besides chaos, the void is the only entity that has the power to temporarily suspend city rhythms. It appears in different spatial forms, from a large, abandoned field like Templehof to an inaccessible rooftop, an unused part of a property, the space under a railway bridge, left-over, unorganized space between high-rise buildings, unused public space, etc. The void can take different forms and occur at different scales, it can be accessible or not, it can last for centuries or minutes, but its most important feature is its regenerative potential triggered by its undetermined use. Chaos, on the other hand, is time-related, and potentially destructive to space. It can occur at different scales, through natural hazards or man-made events like sieges, bombings, fires, up-risings, or, at a smaller scale, transgressions of use, non-organized crime, car accidents, blackouts, etc.

The Void and the Chaos defy the city as an organized spatial and temporal system of human activity. They represent therefore a threat, and one always present because generated by the city and its environment. Consequently, the natural reflex of organized live is to quarantine void and chaos by isolating and supervising them, with the long-term objective of elimination. Yet, contamination doesn´t necessarily mean destruction, it can also constitute a source of renewal for the city-rhythm. What if void and chaos, even at the smallest scale, were to be perfectly contained? What if the city-rhythm were to be perfectly and knowledgeably managed? Wouldn´t this lead to sterility and oppressiveness? Wouldn´t such a city be unable to keep up with time, create novelty and host life? An instant of denial can be a spark of renewal. When chaos meets the void, entirely new systems can be created.

What if, instead of putting so much effort in defining the future of Tempelhof, and in managing its huge surface as a coherent whole, chaos would be let in, simply by giving the land away to free use and construction? What kind of repressed forces of the city surrounding it would take over and what new worlds would they create? The subversive potential of such an experiment is big enough to make the question too scary for all parties involved in the discussion: the residents of the surrounding neighborhoods, the city´s administration and the potential investors. This makes it hard for the empty field of Tempelhof to fully exercise its transforming influence on the city.

However, since a one-sided top-down solution is hard to achieve for a surface of 386 ha, time will probably allow for a more diverse involvement in the definition of its uses. The more original the uses and the more diverse the actors, the bigger the success of the void. In the meantime the number of abandoned airports around the world is on the rise, only in Berlin, a second airport, Tegel, is set for closure next year. Exactly what changes will this huge land resource bring to the city is hard to predict.

Stapleton International Airport, Denver, USA - opened: 1929; - closed: 1998 - current state: masterplanned community

Kai Tak Airport, Hong Kong, PRC - opened: 1925; - closed: 1998 - current state: abandoned after several masterplanning attempts

Nicosia International Airport, Nicosia, Cyprus - opened 1939; - closed 1974 - current state: abandoned in the UN buffer zone

Berlin Tegel “Otto Lilienthal” Airport, Berlin, Germany - opened (as a military airport at first): 1906; - to be closed in 2013 - current state: in use