1. Sun Tzu said: The control of a large force
is the same principle as the control of a few men:
it is merely a question of dividing up their numbers.2. Fighting with a large army under your command
is nowise different from fighting with a small one:
it is merely a question of instituting signs and signals.
- From The Art of War by Sun Tzu
The problem of social cooperation is how to order many individuals into large-scale patterns, and thus acquire the benefits of these larger patterns. The military arts were the first to face this problem, war being a field where inferiority carries severe consequences, and lessons are learned quickly. The solution was known in the time of Sun Tzu: the superior army was the one that could act as a single force, applying a single decision multiplied by however many men were at the command of this army. More men were always better, but past a certain scale it became unmanageable for a commander to yell out orders to everyone and maintain command. In order to resolve this the military men invented hierarchy, a command structure through which the commander’s orders would be distributed so that a group of any size could act as a single force.
For most of history success in war came from achieving and maintaining organization, lines of command from a center to the individuals that compose an army such that the commander could deploy the army in the most effective pattern he could think of. Discipline and complete obedience to orders was required, even if the situation as it appeared to the lowly grunt was in total contradiction to the orders he had been signaled. As far as he knew, the commander had a larger picture of the war and the orders ought to work out correctly. But the flaw in organization is that as an organization becomes larger, as the layers of hierarchy increase, the commander becomes more remote and more isolated from his army. The lines of communication become inefficient, the orders become irrelevant, and many men die stupidly.
Nevertheless, for centuries the sheer overwhelming force of numbers more than made up for the losses due to bad orders. The principle of organization triumphed. Reformers started looking for plans to organize industries, entire nations (the command economy of the Soviet Union), and of course, cities. The C.I.A.M. Athens Conference resulted in the publication in 1942, by Le Corbusier, of the Athens Charter, the document upon which the plans to organize modern cities, and be rid of the spontaneous historic city, were founded.
Between the time of the Athens Conference and the publication of the Athens Charter, the military concept of large-scale organization was completely discredited.
In June 1940 the German army invaded France. The two armies were evenly matched in men and weapons, France even having a advantage in tanks. Within one month the French army organization collapsed and millions of men surrendered without having put up much of a fight, resulting in many decades of American jokes about French surrender. In reality the two armies were far from evenly matched; the German generals had discovered a mean to overcome the weakness in the principle of organization, that it relied on a central, single commander. Their model of cooperation has been called Blitzkrieg, the lightning war, and its intent was to reduce the delay in receiving and sending the “signs and signals” of command by removing them. German commanders out in the field were given broad directives and trusted to figure out on their own how to fulfill them, with glory and medals as reward for success. The French had instead refined organization and bureaucracy into a precise art. Within days of breaching into France, autonomous German tank divisions destroyed the lines of communication of the French army and paralyzed the front-line units. It became impossible for it to act as a single force, never mind stopping an invasion.
The German system of directive command was in fact the universal principle of emergence applied to military action. Instead of building a hierarchy of orders to communicate the will of a central commander, the armies were organized in parallel, directed to respond to their observed context, a context which was itself produced by other units of the same army. Instead of deploying the intelligence of a single commander holed up in an office in Berlin, the German system linked the intelligence of all of its officers into a more effective super-intelligence that could see all of the battlefield simultaneously. The collapse of the French army was therefore inevitable. It was a case of one against many.
As already mentioned, war teaches quickly, and the allies eventually adopted a similar operations model to fight the war to victory. German operations theorists went on to design the structure of NATO’s European defense, a war that we fortunately never witnessed. Urban planners did not have to learn this lesson, and they opted to organize cities to ruin.
The network structure is often, incorrectly, called a “bottom-up” organization. My opinion is that this label makes no sense. There is no up or down in a network. There is neither bottom nor top. Those are descriptions that apply to hierarchies only. In a network actions happen horizontally, in parallel. Large-scale patterns are made up of links between those local actions, as seen in the figure above. Human intelligence, for example, cannot be explained as a collection of cells. It is the patterns formed by the links between these cells that is intelligent, and it is these patterns that allow us humans to be several orders of magnitude more complex than individual cells.
The paralysis inflicted on the French army organization was in parts self-inflicted. Longer chains of command involved delays in transmitting information (reports from the field), analyzing the information, planning a reaction and ordering the new deployment. The bigger the army became, the more paralysis it suffered. This organization was in much the same situation as the dinosaur who did not feel a hit on his tail because the nerves were too far from his brain. The bigger it became, the more exposed it was to a paralysis-focused attack.
It should not come as a surprise that what caused the death of cities is also self-inflicted paralysis. But the case of cities is much more tragic. The German operations model was novel and innovative, a radical improvement in military art. Cities, however, had always been emergent. They were the product of a spontaneous order, a phenomenon that was barely understood at the height of rationalist planning. What science did understand was organization. Since it was accepted as the pinnacle of science, no rational thinker could reject the new urban planning. The planners did not notice the hints: what they were organizing had not been a creation of anyone.
In a complex emergent system, the number of unique patterns scales up with the size of the system. (What some emergence commentators call “more is different,” another expression that makes no sense.) While an organization attempts to create a large-scale pattern to outmatch smaller patterns, a complex system is made up of both small and large patterns, in proportion to a power law, either nested together or juxtaposed randomly (a fractal). If an emergent system is intelligent, it will structure itself into patterns that no one had expected.
For centuries people had been accustomed to such patterns as the street of similar shopkeepers. Many streets in European cities bear the name of a particular trade, such as baker’s street or threadneedle street. But when cities passed a critical scale during the industrial revolution, a whole new pattern emerged: the central business district. An entire city within the city became the center of commerce, not simply specific streets next to residences. Although it appeared unexpectedly during the 19th century (the Haussmannian renovation of the Opera district of Paris was meant to create a neighborhood for the upper classes, but it became a business center immediately and has remained so ever since), a central business district came to be what a major city was all about. When planners set out to organize a modern city, they planned it around the CBD as the central feature. They did this by drawing a square on the map and applying a different set of rules to this square. Within a few years, their CBDs began dying. The small scale patterns nested within them had been zoned out.
In retrospect it was inevitable for an attempt at organization to severely interfere with urban processes, the principle of organization being a step down in complexity from the principle of emergence. Organization had a sinister advantage: it gave the planners the illusion that they could predict what the city was going to become. An emergent system cannot be predicted with precision. The very basis of its intelligence is that it has not yet been decided what it is going to do. Embracing an emergent system means accepting that patterns will appear that are beyond our comprehension. (In Wolfram’s terminology, the system is computationally equivalent to our own intelligence.)
By trusting their front line officers to run the war for themselves, the German general staff took a leap of faith that paid off decisively and confronted every opposing military with their crippling inferiority. I suspect the first modern city to give up on the principle of organization will trigger a similar revolution.
Modeling the processes of urban emergence
The growth process of an emergent city actually consists of five growth processes. These processes are hierarchically related, that is to say the morphology decided by processes at higher levels of complexity depends on decisions taken at lower levels of complexity. They are not constrained by one another, as modern planners claim when they clear slums in order to build their architectural vision, but expand upon one another, creating a landscape that is tied to a history of adaptation and transformation in order to meet the needs of the present at every point in time.
Each transformation is the decision of an individual, acting within the context he perceives and the ends that are identified. These ends may be within his own sphere of life, by expanding his home, or subdividing his property to build a home for his grown children, but more likely they are the consequences of identifying a potential created by the individual actions of others. For example, if a sufficient number of neighbors have settled, opening a bakery. In this way networks are built upon the potentials created by the last network extension, (in one such instance by capturing residual movement in the grid as Bill Hillier describes) and the city increases in complexity.
The foundation process of a city, before anyone can even imagine a city being there, I call the place. A place is nothing more than a free surface available to be settled. Newcomers build their home wherever they want in the place, and that implies that they will locate their homes to take maximum advantage of natural features, and space themselves away from their neighbors in order to avoid conflicts over the use of common lands. A place settlement process is how shantytowns are created, except that because there does not exist any functional land ownership in a shantytown there is no limit to how many buildings can be created. Thus the shantytown never reaches the second process of urban emergence, creating a crisis. A place may be created deliberately, by transforming a farm or other types of land use to that purpose, by building fortifications within which land is protected from harm, or a place may be given by nature simply by being available and strategically located.
A place is an open space where people may settle and build randomly
As places become increasingly dense, the use of space by neighbors will create conflicts of proximity. Land will no longer be superabundant. In order to resolve these conflicts a process of land enclosure delimits the boundaries between neighbors’ households by negotiating the boundaries of land that is in private and common use. Streets and blocks thus appear, and those spaces where common use is particularly intensive, because of highly valuable natural features or central locations, become recognized as public squares and greens.
Enclosures delimit private and public spaces, and the pattern of streets, blocks and squares emerges.
With available land to settle either enclosed or occupied by public activities, it becomes more difficult for new growth to take place. New buildings built on remaining place must be justified before a community increasingly protective of the remaining open space. In most cases it is much simpler to ask one of the members of the community to give up a part of his property in order to grow the new part of the town, introducing the process of subdivision. These subdivisions are negotiated case-by-case and thus adopt random sizes and shapes, creating a fractal distribution of lot sizes over a long timeline. Some subdivisions split the land into shared courtyards and cul-de-sacs that are administered under a co-property agreement (they never need to involve the community as a whole).
Properties are subdivided to make room for new growth and new network relationships now that open land is in short supply.
Eventually crowding becomes problematic at the same time as the scale of network growth is increasing due to higher population densities. This creates the opportunity not only to open new places to settlement, but also to connect the central city to these new places by a place functioning at a greater scale, near a road or highway, and that provides an encircling bypass around smaller-scale neighborhoods. This is the grid process. This new construction opens up land to construct large market and industrial businesses that are simultaneously a buffer between smaller-scale places and roads but also an integrator of these places into larger-scale networks.
The grid integrates mature places into a larger network of places, and creates new spontaneous development opportunities.
The last process takes place when a large city with many places integrated by many scales of grids develops a mass transit system that becomes more reliable than private transportation systems. When that occurs the need for private transportation falls radically and it becomes possible to live at the centers of this mass transit system without any private transportation, thus radically reducing demand for space. Parking lots can be built over and turned into undifferentiated buildings providing standardized living spaces that can find their match in the very large population. This radically higher population in turn creates a very wide potential for new differentiated networks, and the construction of large buildings is accompanied by many new, differentiated small buildings. This is what enables a place to achieve high density complexity, and we can call it the metropolitan process.
A small number of larger new buildings accompanies a large number of small new buildings resulting from the reduction in space needed for transportation.
A model such as this one is not meant to be a design to be implemented in reality. It serves only as an illustration of the processes, the means through which decisions are achieved, that generate the structure of cities. If we want to do the morphology of an existing city, it is these processes that will help us explain what decisions led to the city’s present form. These processes also help us predict the future of the model of urban development we choose to adopt. As an example I have become highly critical of measures that seek to increase the density of subdivision developments by smart growth zoning regulations. They tend to leave the structure of neighborhoods in such a state that further subdivision processes within its tissue are impossible, and the neighborhood becomes unable to adapt itself as its population changes. Instead we should be building low density subdivision developments that can grow naturally into metropolitan neighborhoods, and this growth will be controlled by its community as its members make the decision to give up a part of their property to accomodate the changes the community is undergoing.