Tag Archives: emergence

Chaos re-emerges

1960’s psychedelic art?

landscape-chaos

Or the American landscape?

Notice how much negative space is created by the imposition of the grid on a chaotic reality. The simplicity of the cartesian plan is deceptive. It generates complications as the random process of change unfolds.

Decoding paradise – the emergent form of Mediterranean towns

scarano4

Serifos in Greece

Until very recent times, a study entitled Julian of Ascalon’s Treatise of Design and Construction Rules From Sixth-Century Palestine might have been categorized somewhere in-between ancient history and archeology of architecture, if not relegated to the dusty shelves of legal scholarship. Although it deals with one of the most sought-after secrets of architecture, how to build the charming Mediterranean towns of Greece, Spain, North Africa, the Near East and many other places, this is not immediately obvious from the content of the treatise. The reason for this is that the treatise does not so much describe the form of the town as the process for building it, and the process turns out to be emergent. Unless the reader makes the link from process to form, the rules described will make no more sense than the rules for a cellular automaton out of context.

It is tragic that enormous amounts of resources have been spent attempting to recreate the Mediterranean town with no clue as to the underlying source of its complexity. Montreal itself has the world famous Habitat 67, a confusing pastiche of the memories that architect Moshe Safdie brought back from his land of birth, which he had in common with Julian of Ascalon. Habitat 67 was intended to be a low-cost solution to housing, but it never was taken seriously as a model for urban habitat, and its current untrendiness spares it from being labeled fake complexity. That an attempt to emulate the architecture of some of the poorest people of previous centuries would result in an expensive failure testifies to the inadequacy of modern production processes, but also of the wealth inherent in those simple traditional production processes. The beauty resulting from large aggregations of simple buildings has turned many towns into tourist destinations. There is value in process.

The complexity demonstrated by the constructions of pre-modern civilizations may be a direct consequence of their material poverty. Most people will claim that the loss of building quality is a result of culture, and so we must change our own culture through education. That is not a complete answer. Cultures are stored in information technologies and media. The modern era coincides with the invention of printing, making it possible for the first time to reproduce information in large quantities at low costs. As information technologies have progressed and become more affordable, building processes have become increasingly dependent on large amounts of descriptive information, with blueprints describing in every minute detail how to compose a building. And now that CAD software can describe and store nearly limitless information, whole new forms of buildings have become possible.

All of this progress has only enabled builders to become lazier with information. Pre-modern builders, limited to oral communication and their brains to hold information, had to employ very sophisticated means of information compression to communicate and simply remember their cultures. This lead them to rely on simple processes the likes of which are behind the complexity in fractal geometry and cellular automata to build their environments – very short sequences of information that can be utilized to generate fully complex forms. Christopher Alexander even used as an example, in The Nature of Order, the production of a boat that had been coded into a song that the builders recited while creating the boat, adding a mnemotechnical aspect to the storage of cultural information that was essential to pre-modern survival.

Without knowing how traditional cultures were stored, we had no idea how to inspire ourselves from them. Modern and post-modern architects attempted in vain to imitate traditional building using their own, lazy information technologies, and succeeded only in building pastiche of complexity. The breakthroughs in complexity theory of the past decades finally gave us the opportunity to decode the mysteries of historic building cultures by showing us what kind of information to search for. What was right in front our noses suddenly becomes deeply meaningful.

It is to his great credit that Besim S. Hakim went looking specifically for the source of the emergent forms of Mediterranean towns in treatises of building laws. From his study of the treatise of Julian of Ascalon, but also of those of Muslim scholars around the Mediterranean, he was able to identify the underlying process that generates the complex morphology all towns of the region have in common, and that so many have sought to imitate. It is no exaggeration to call this pioneering work in complexity.

The space of Hakim’s search began in the Islamic world, with the treatise of Ibn al-Rami from Tunis in circa 1350. Tracing the origins of the practices described in the treatise, references to treatises written in Egypt, Arabia, Tunisia and Andalusia in previous centuries were researched until the treatise of Julian of Ascalon was uncovered. Written in Palestine to describe the local building customs in order to provide the Byzantine empire with an improved legal system, this particular treatise’s value is its longevity. After propagating throughout Greek civilization as part of a general book of laws (the Hexabiblos), its authority was invoked in decisions dating as recently as the 19th century. Hakim infers the origins of these shared practices, and the shared morphology of regions as far apart culturally, linguistically and geographically, as Andalusia, Greece and Palestine, to customs from ancient Babylonian civilization that had spread to the Eastern Roman Empire.

The goal shared by these treatises is a definition of urbanism as relevant today as it was in Babylon:

The goal is to deal with change in the built environment by ensuring that minimum damage occurs to preexisting structures and their owners, through stipulating fairness in the distribution of rights and responsibilities among various parties, particularly those who are proximate to each other. This ultimately will ensure the equitable equilibrium of the built environment during the process of change and growth. (Hakim, Mediterranean urban and building codes: origins, content, impact, and lessons, p. 24)

Here we see what the underlying error of Habitat 67 was. It was designed as a single static building imitating a process that made a living tissue out of many individual acts of simple building. The codes of the Mediterranean treat the town as a living, whole structure in movement that must be preserved while it achieves equilibrium with a changing environment and society.

Perhaps the most relevant conclusion of this research is the identification of proscriptive and prescriptive rules for building.

Proscription is an imposed restraint synonymous with prohibition as in ‘Thou shalt not’, for example, you are free to design and manipulate your property provided you do not create damage on adjacent properties. Prescription is laying down of authoritative directions as in ‘Thou shalt’, for example, you shall setback from your front boundary by (x) meters, and from your side boundaries by (y) meters regardless of site conditions. Byzantine codes in many instances included specific numeric prescriptions, unlike their Islamic counterparts that tended not to include them. (Hakim, Mediterranean urban and building codes: origins, content, impact, and lessons, p. 26)

A prescription would be a rule that defines in detail what to do in a given situation. A proscription is a template for defining prescriptive rules, a pattern for a rule. Muslim scholars provided mainly proscriptions, but Julian of Ascalon’s treatise was highly prescriptive. Julian was describing in details the local building codes with the idea that they would be used to devise proscriptive rules for the empire. By accident these prescriptive rules became law and remained in force for centuries until their inability to deal with society or physical conditions radically different from sixth century Palestine made them obsolete. Although it means the codes failed to deal with changing circumstances, this gives us the chance to bridge the gap between the physical structure of built towns and the rules that generate them.

The concept of proscriptive rules also helps explain why so many different cultures with specific structural typologies can generate such similar morphology. Hakim uses as an example the problem of views. The Greeks were preoccupied with views of the sea, and their prescriptive rules obliged the preservation of view corridors in new constructions. Muslims, on the other hand, were preoccupied with the preservation of privacy and the prevention of intrusive views from one property to another. This would have very different results structurally, however those two prescriptive rules are based on the same underlying proscription. Local customs and culture could therefore be translated into prescriptive rules using the proscriptions inscribed in building treatises and the emergent morphology of those proscriptions would be symmetric from one culture to the next, while being fully adapted to local conditions.

Another significant fact that strikes out from these treatises is the importance of relationships between neighbors. The Julian of Ascalon treatise describes how to literally embed houses into each other, ultimately making them one continuous, somewhat random building created through iterated steps. But most importantly by proscribing rules as relevant to a neighborhood, Mediterranean urbanism avoids the problem of the absolutist, dare I say “Cartesian” rules of modern planning that are relative to the precisely subdivided lot the building is on. Hakim shows the wastefulness of latter rules in a comparison of the old town of Muharraq in Bahrain with a new subdivision from modern Muharraq.

hakim1a hakim1b

The town on the left was generated using proscriptions based on neighbors, while the subdivision on the right used absolute rules planned with the subdivision. Notice that the configurations on the right waste much of the space in order to achieve a strictly Cartesian, grid-like morphology that no doubt looks orderly to the planners.

The last item of significance, and perhaps the most revolutionary, is how the proscriptions extracted by Hakim are similar in nature to the rules that Stephen Wolfram described to generate emergent complexity with cellular automata. He himself follows a proscription/prescription system, where the proscription is for example the 2 color, one-dimension elementary cellular automaton that made him famous, for which there exist 256 different prescriptive rules of neighborhood, some of which grow in time to make two-dimensional chaotic fractals. Some urban complexity researchers such as Michael Batty have been playing with cellular automata trying to reproduce urban form, but their efforts have taken them on the wrong track. The codes of historic towns behave in the same manner as a cellular automaton. This should be the focus of their research.

Whatever the potential for research, the proscriptions discovered by Besim S. Hakim are still relevant today and can be used to create the prescriptions that we need to implement an emergent urbanism relevant to the problems of today, that is to say the creation of a sustainable city and living urban tissue out of the vast urban fabric of suburban sprawl. Hakim has so far focused his work on the regeneration of historic neighborhoods by restoring the generative codes that produced them, but there is a vast potential to expand his work to non-historic neighborhoods that are in dire need of new life.

Addendum

Four regions, four cultures, one shared process generating a symmetric morphology

sidibousaid

Tunisia

mojacar-from-the-air

Andalusia

scarano1a

Greece

palestine

Palestine

Reference

Besim S. Hakim – Generative processes for revitalising historic towns or heritage districts

Besim S. Hakim – Julian of Ascalon’s Treatise of Construction and Design Rules from Sixth Century Palestine

Besim S. Hakim – Mediterranean urban and building codes: origins, content, impact, and lessons

and don’t forget to look at Besim S. Hakim’s website.

Mr. Besim S. Hakim provided comments for this article

Picture from Alessandra Scarano were also used

Producing land with nested markets

The Poundbury Grid, from Streets and Patterns by Stephen Marshall

The Poundbury Grid, from Streets and Patterns by Stephen Marshall

When the modernists unleashed their program for simplifying cities, they did not limit themselves to redirecting existing institutions. Within the modernist ideology was implied the idea that transportation, open space and buildings were separate, isolated things and could therefore be made in isolation. This lead them to create entirely new institutions that operated independently. One of these was the Department of Transportation, also called Ministry of Transportation, or Délégation Départementale de l’Équipement, or somesuch. Its mission was clear: build roads, make them fast, clear away all obstacles and let’s drive. While the collapse of the modernist program in architecture swept away the building typologies they had invented and would later make room for the creation of such architectural artifacts as Poundbury, the transportation system they had devised continues to operate unchallenged. This system, it must be realized, is sprawl. It is the engine of urbanisation throughout the world. It does this by taking rural land and upgrading it, without any conscious realization of what it is doing, into urban land. The very existence of Poundbury, or any other New Urbanist development, is owed to this urbanization. Without it, it could not have any economy. It is therefore incorrect to refer to it as only a transportation system. It is a land production system, creating markets for land where there were none before.

Writer Alex Marshall (not Stephen) correctly diagnosed what was occurring in How Cities Work. In it, he identified the architects and planners of economic powerhouse Silicon Valley as being the state and federal transportation agencies, and invited New Urbanists to work for these agencies if they wanted to have an effective impact on the design of cities. While his book is an illuminating exploration of the processes for building cities and even lays the groundwork for an emergent theory of urbanism, by the middle chapters Alex Marshall seems to lose his mind and lays the blame for the urban mess on market ideology, Republicans and the almighty Libertarians. If only government authority over land was unrestricted, and the voters (I presume) realized that an urban planning system is a choice and not an inevitability, then once again real cities could be made instead of sprawl.

I appreciate his arguments in favor of making better, more informed, richer choices in how cities are planned. But the fact that the tone of his book radically shifts from cool, rational analysis about systems for urbanisation to anger and blame over restrictions imposed on government authority shows that he has disentangled one layer of confusion about cities only to expose another, even more entangled layer: that of land ownership and market creation. To see through that layer requires traveling back in history to the very beginning of the industrial age and farther.

Our ancestors in America lived almost exclusively as homesteaders and independent land owners. The appeal of migrating to the new world was the abundance of homesteadable land. At the beginning of the 19th century, places such as New York City were shipping towns of little importance relative to the agrarian economy. This was not the case in Europe, where the land was owned in very large estates by a small number of aristocratic families. The rest of the population lived upon the land as tenants. Cities also were estates, with those not owned by the aristocracy being owned either by the clergy or by corporations of merchants chartered in the middle ages. (The City of London somehow miraculously continues to operate by this system.)

The fact that Europeans and Americans had a vastly different starting point in land ownership affects the way they conceive of municipal authority. Because land estates always regulated tenants and built improvements such as roads to collect rents, Europeans will see the city as a public service and consider zoning and regulation as completely normal and legitimate. In America every man was his own land owner. Land rents, roads and zoning were imposed through the force of government upon those small land owners. Because of this, Americans see the city as a government interference and resist zoning and regulation.

The suburban dream, to own one’s house, has come to replace the American dream, to own one’s land. But the economic reality of owning a parcel of land and being a landowner are completely different. Our ancestors lived from their land, not simply on it. Their wealth came from their land. A house owner simply resides on his property, he does not live from it. His living is made from his participation in the life of the city, and he needs the roads in order to do that. Should the road to his house be blocked off, either intentionally or by natural accident, the house would become useless but he would not lose his living. A house owner is as much a tenant as his European ancestor. He rents the streets he lives from.

The relationship between transportation and land rents has been known forever. In the late 19th century railroad developers created new neighborhoods of cities by buying up isolated land, extending the railroad to it and then parcellating it into lots. The people of this new neighborhood lived from the railroad commute. The development of Los Angeles is famous for having been driven by streetcar companies expanding to new areas and profiting from the land they improved. The ownership of the streets was then transferred back to city corporations. It was moved from private to communal ownership, with all the pitfalls this implied.

Seeking to increase the value of their developments by adding a more restrictive layer of controls over the subdivisions they produce, developers have for the last few decades been creating home owners’ associations to provide for the roads and control covenants upon the private parcels of home owners. In doing so they have chosen to take an alternative course to municipal incorporation, but unfortunately the organizations have shown themselves to be draconian in their application of rules as banal as the height of lawns and in so doing compounded the reputation of suburban subdivisions as zones of conformity. The HOA is a cooperative ownership model that transforms subdivisions into structures as rigid as a condominium tower, without the material rigidity of the tower itself. If one is an advocate of the suburban subdivision in the name of freedom, this model seems to miss the mark.

It is indisputable that HOAs provide a good, environmental control, that home buyers wish to have. They are willing to give up control over their house in exchange for part control over the neighborhood. The developers are creating neighborhood value by tying their product into a system of rules, and in doing so increasing the demand for the individual homes. Developers are creating rules-constrained markets within the framework of the HOA, a cooperative of home owners who pay a rent to have the right to be part of this market. The HOA market itself exists within the market created by the road that integrates it to the productive economy, road which has almost certainly been created by a municipality or county administration. It is a market within a market, and both have their specific rules as to how land may be utilized.

Alex Marshall claims that market creation is the exclusive domain of government. I believe this is dangerously incorrect, not out of anti-government bias but because the organization of government places strict limits on the complexity of the markets that will be created, something that we both appear to agree is a major flaw of our urbanism. To show this, I will explain the history of one of the weirdest cities of Paris, the business district La Défense.

almost-utopia gare-grande-arche noeud-gordien-ii

The most peculiar aspect of the city is its organization of land. It was founded in the late 1950’s and planned in the early 60’s in the model of utopian modernism, which meant strict separation of pedestrian and vehicular traffic and rows of identical tower blocks. The master plan rapidly fell apart and was abandoned when it was realized that the companies for whom the towers were meant had no use for them in their planned shape. From that moment they were free to define what kind of tower they wanted to build, however the system of traffic separation remained. The developer proceeded to build an enormous structure (about three stories tall) over the natural ground called, roughly translated, The Slab. The Slab is the main pedestrian space that integrates all the towers into the mass transit network of metropolitan Paris and the commercial activity of the district. The centre of The Slab (seen left) turns out to be the ceiling of the gigantic mass transit station (seen middle) that distributes 150,000 people to and from their offices morning and night. The buildings at La Défense do not have any connection to land or streets, they float upon The Slab.

This project is said to be one of the flagships of the French state, but the interesting thing about this is that the state had to go around its own system of land administration in order to create it. Municipalities in France are organized around 36,600 communes whose statutes regarding urban planning and land use are strictly defined in the legislation of the administration. La Défense does not have an administration in the same sense that communes do. It was created as a national interest operation, meaning that the state, realizing that its own territorial administration system could not deal with a project of such complexity, declared a zone of territorial exception where the legislation was suspended. Instead, the land inside the zone was purchased by a developer, the EPAD, whose statutes are defined by private business law but whose majority shareholder is the state. In other words, the state had to go through the market to avoid flaws in the system of government in order to create a market unlike anything the country had seen before.

The EPAD has since operated profitably by investing in land improvements, most importantly paying to bring regional rail and metro links to the district, and selling development rights for towers that are limited by contract to certain open-ended morphologies. No one owns land there except EPAD, but private companies do own their buildings. Those buildings never could have been built had EPAD not created a market for them through the expansion of the mass transit network it paid for, and of course by building The Slab.

EPAD, an organization who was meant to last at most 20 years, celebrated its 50th anniversary this year while many people struggled with the “outlaw” nature of its existence. Proposals for reform all crash against the challenge of The Slab and how it could continue to function as a form of urbanism within the framework of standard territorial law. This territorial law is itself being questioned and most likely headed for reform, although there is no guarantee that reformed law will be competent to handle a structure of this nature. The way things are going, it’s possible that EPAD could have a longevity comparable to the City of London.

The lesson of La Défense is that for-profit enterprises can create urbanism, markets for land supported by large capital structures, provided that the law allow them to. In other economic sectors this arrangement is nothing unusual. To persuade Republicans and Libertarians of the benefit of urbanism, it suffices to make a comparison with the New York Stock Exchange company, an icon of capitalism. While the service the company provides is a means to trade stocks efficiently, this service does not come free. The NYSE occupies some valuable real estate in downtown Manhattan, and provides sophisticated computer equipment and trading services to participants. You must pay for your right to take part in the NYSE, and then obviously must pay again to buy shares. Your ability to trade shares may not be possible without the supporting capital investments of the NYSE company. The NYSE, although it creates a market, is itself competing in a bigger market, that of stock exchanges. It must be better at enabling stock trading than other stock exchanges in order to attract traders and companies, and it can itself be bought, sold, merged or spun-off as a company. The stock trades are a market that is nested within the market for stock exchanges.

For the liberal-democrat wary of such fine capitalist institutions, the work of market creation can also be done by a non-profit organization. This is what one of my favorite examples, the Wikimedia Foundation, does with its different wikis. Although the trades are free, the foundation does provide the framework for people to rapidly and easily share and structure information. A foundation which owns land could in the same way create a market for buildings by enabling its inhabitants. It is exactly such a process that Christopher Alexander described in The Oregon Experiment. By his proposal, the University of Oregon was required to provide design assistance to faculty and students who wanted to initiate building projects. This form of market would obviously put enormous power in the hands of the users and less so in those of big developers, which is the opposite of what municipal planning systems have done.

Municipal planning systems, as we have known them for the last two centuries in America, have been held up by two pillars. The grid of streets and later on the supergrid of arterials have urbanized land in a manner that favored land speculators and developers, and then the large land speculators and developers. The second pillar has been the zoning ordinance and building code, a system of bureaucratic regulations that has grown in size to the point where consultants must be hired to navigate the process. The non-professional who wants to build something in this market, if he has been lucky enough to benefit from the grid, must first understand a stack of regulations that will take him enormous effort to master. This cost evidently favors developers who have a lot to invest in building and discourages the creation of the small events, quirky house, shops and businesses, that make a city so pleasurable. Bureaucratic regulations also have the nasty side-effect of being unable to translate qualitative standards into rules, the result being a long list of quantitative regulations that produce big subdivisions, big malls and big business. The SmartCode, 60 pages long, does not improve upon this process. It makes the big subdivisions take a different shape.

Paris' 16th borough (front) and La Defense (back)

The 16th borough of Paris (front) and La Défense (back). Two different markets creating two different emergent morphologies, and different environmental qualities as well. Those are choices.

The creation of the municipal system in Europe was an act of land reform, breaking down land estates that had their origins in feudal privilege. The French communes were the product of the revolution, and the municipal corporations acts of Great Britain in the 19th century put an end to quite a few “rotten boroughs.” The end of the feudal tenure system could be justly seen as progress by Europeans, and the new powers wielded by municipalities did not exceed those wielded by the previous landlords. In America the incorporation of land into municipalities, and the transfer of ever greater powers to county governments, took place at the expense of small land owners who considered themselves independent and resisted the limitations imposed upon them by new municipal regulations, while profiting at the same time from the new markets created for their land by investment in structural improvements, most of all roads. Both processes for creating municipalities have since been the monopoly of governments, and the slow action in creating, dissolving, merging and splitting cities has caused crisis in all areas. Alex Marshall points out that state governments have the authority to create and merge municipal corporations, and should make use of this authority more often, but governments only have limited attention to devote to these issues. In the early 19th century it required an act of government to charter any business corporation. The regularization of this system allowed businesses to incorporate without going through the legislative process, and the dynamic market economy we have enjoyed since has this process as one of its foundations. For some reason it was never thought of to extend the same rights to city corporations.

In their pleas to “leave things to the market” Americans severely restricted what kind of operations municipalities could undertake, and limited their authority to take action against public problems. In doing so they did not realize what kind of market was being created, and who would benefit most from it. A municipality that does more is no less of a market than one that does less. A municipality that builds a hierarchical grid of differently-scaled streets and helps non-professionals to create their own buildings would be creating a market, and ultimately an emergent urban morphology, vastly different from what limited municipalities have been allowed to create. More restrictive rules could also create environmental quality that would raise the value of the market as a whole. The municipality could be creating a better market than it currently is if it had more freedom to act.

Inventing and organizing such a municipality will itself require a process that systems of government cannot handle. This is where things truly ought to be left to the market. Independently owned and operated cities could adapt and reorganize themselves to experiment with new forms of markets. They could merge and spin-off to meet the challenges of metropolitan scale. They could buy the land that they intend to urbanize. They could regulate the land to preserve the quality of the environment and create greater neighborhood value. They could make the immense capital investments in roads, mass transit, public squares, parks and utilities that would earn them a profit in increased rents from their markets. Finally, the disintegrated land creation institutions brought about by the modernist program could be reintegrated in cities with enough authority to employ them efficiently and productively.

Sprawl would soon after be a footnote of history, along with many other urban ills.

References

How Cities Work by Alex Marshall

Streets and Patterns by Stephen Marshall

The Oregon Experiment by Christopher Alexander

Creating the emergent dimension, or learning from Wikipedia

In Architecture: Choice or Fate, his manifesto for New Urbanism, classicist Leon Krier produced many inspirational images of urban complexity, going as far as a fractal comparison of modern and traditional buildings. The cover of the book, a fictional resort town for Tenerife, presents a fascinating case study of complex symmetry; no building is the same as another, but all share the same geometric properties. That would not be unusual had it not been an architectural manifesto. Competent artists have always been able to imagine dream cities, and they continue to do so with every blockbuster fantasy movie that hits the screens.

The dream city of Coruscant in Star Wars

The dream city of Not London in The Golden Compass

Like the dream cities of Le Corbusier and his modernist colleagues, the dream cities of artists have in common the fact that none of them have ever been realized. Leon Krier’s dream city, Poundbury, has been realized by the capital backing of a supernaturally rich patron, and even then it has been built very slowly and carefully. In the time it has taken to develop Poundbury, millions of urbanisations have occurred elsewhere. Like the New Urbanist TNDs of America, no matter how much we enjoy their architectural quality, we cannot consider them to be real cities. The real city has been built in the emergent dimension, not by the mind of a single artist but by the material necessities of all people. While it is fairly straightforward for an artist like Leon Krier to invent and apply his own form language to imagine a complex cityscape, in order for this design to be adapted to the material necessities of millions it must also involve millions. We obviously cannot burden a single artist with this task.

And so urbanism has a wholly different starting point from architecture. The artist does not have control. No one can possibly ever have control. Everything is happening all at once everywhere at once. To attempt to stabilize this process has caused chaos everywhere.

The starting point of urbanism is the same starting point that the founder of Wikipedia, Jimmy Wales, set for himself when he established the Internet’s now most indispensable website. Instead of asking how to publish the expert opinion of specialists as an encyclopedia that would compete with the print powerhouses (a venture he had already attempted and failed at), Wales based his system on the theories of economist and complexity scientist Friedrich von Hayek. The idea that Hayek proposes is that there exists specific knowledge that only individuals possess, and that can only be utilized with their cooperation. Wales saw his task as the aggregation of this knowledge into one coherent system.

The world-wide-web had, since the early 90’s, become a massively hyperlinked knowledge network that everyone could publish in. The reality at the time of Wikipedia’s creation was that this power had not produced any kind of coherent system for basic knowledge. Aggregating knowledge had up to then been too complicated. Wales wanted, in his own words, to “make the Internet not suck.” Overcoming this deficiency meant simplifying the production of web pages and hyperlinks, removing some unnecessary choices in the process. This is what the interface of Wikipedia did. Within a year, Wikipedia had grown explosively and exponentially. Making information easier to create and access had made it possible for the sum total of encyclopedic knowledge to be rapidly constituted.

This has come at a cost, however. While there is in theory unlimited freedom to add content that one considers relevant to Wikipedia, the form that this content will take on screen is very rigidly defined. This is necessary in order to achieve the complexity of the system. The design of Wikipedia is constant across every page in order to make it possible to rapidly navigate through all the information without having to relearn the rules for every article. Nevertheless, when we click on a link to a Wikipedia page, we never know what we are going to get. The design acts not as a constraint on the content, but as an enabler of the content. Without the rules enforced by Wikipedia, none of the content would have been added.

Wales and his foundation have been extremely controversial. On the one hand, in order for Wikipedia to work as it does, the foundation must provide all the support structures necessary to enable the users to create knowledge, and on the other hand it must also blindly trust the users to create information that will be accurate. It simply is not possible to control the content of so many millions of articles. To attempt this would necessarily shrink the size and reduce the complexity of the system, destroying what makes Wikipedia useful in the first place. The emergent dimension must either be embraced or rejected.

The lessons learned from Wikipedia can also be learned from the very rich past of urban planning. Historically the most successful cities have not been those who have had the least planning but the most enabling plans. The Manhattan plan of 1811, for example, provided for the flexible extension of a street grid without interfering in what could be built within the blocks, and so enabled a surge in urbanisation that was unmatched in history. Eventually this model reached its complexity limits and a new design for Manhattan was applied (with varying success), such as the building codes that gave us wedding-cake skyscrapers, and the metropolitan transit system of subways and later on expressways.

The darker side of this phenomenon has been the creation of city designs that inadvertently enabled the creation of a type of city that no one wanted. Every city, no matter how loudly the local authorities claim to be planning-free, have a design. Take the classical example of a “no planning” city, Houston. Although it has no zoning codes, Houston has a system for laying down a grid of roads that implies necessarily a large-scale, long-ride, automobile-dependent city. By their very form, these roads make some types of urbanisation easier and others more difficult. Who is going to build for a walkable neighborhood when there are no sidewalks? How can a TND make a walkable city when at every mile a thoroughfare cuts off the pedestrian links? How can a sustainable city emerge when only one form of link, long-range auto trips, can be made between destinations?

The threat that we face today is not suburban sprawl. New Urbanism and Smart Growth have been victorious in that aspect. The danger we face is dense sprawl, (see Eric Eidlin, The Worst of All Worlds Los Angeles and the Emerging Reality of Dense Sprawl) where our disconnected cities become denser and denser without becoming more complex, resulting in even poorer urban conditions. The suburb is not the design. Sprawl is the design.

Our cities may not be what we wanted, but they have not been accidents. They are the result of designs applied by the local (and sometimes not-so-local) authorities. They will only change if we invent and apply new designs for them. They cannot be architectural designs founded upon control of the artist. They also cannot be the endless grid of highway strips. Yet they must have both art and highways. It is a whole new method of design, emergent design, that we must master.

Reference

Wikipedia and Beyond: Jimmy Wales’ sprawling vision

The emergent dimension, or why New Urbanism is not urbanism

There are two methods for producing fractal geometry. The first method, the decomposition, is the most easily understood. In a decomposition we apply an algorithm that breaks up the geometry of some starting point into several parts. We then re-apply this algorithm to the smaller parts created, obtain many more, even smaller parts, and continue this reiteration until we have reached the complexity limit at the smallest scale of object we can possibly make. This is how an architectural design proceeds because it reflects the way that building proceeds. A building has a hierarchy of dependencies that begins with the largest structure, the frame. The building is then built with smaller and smaller components until we reach the smallest, for example door handles and light fixtures.

The other method is the composition. In a composition we also apply an iterative algorithm, but instead of breaking down the initial geometry, we expand it. The fractal grows out instead of growing in. This is how urbanisation proceeds, by composing new streets and buildings onto an already existing web of streets and buildings, until we have reached the complexity limit of the largest city we can support.

If we look at this compositional fractal we see that the scale of the structure composed to the initial geometry increases exponentially. The largest structure comes last.

Many of the elementary cellular automatons discovered by Stephen Wolfram produce this fractal using only one dimension of instructions. Each cell, depending on its state (black or white) and the state of its left and right neighbors, applies the rule to determine its new state. A new line is written for every iteration of the algorithm on the previous line. The complexity of the structure only becomes visible when the time dimension is displayed. At their local scale, the cells are not able to “see” how their actions create the system, but their actions do in fact make something bigger than themselves. They are creating a structure by emergence, and this emergence is visible only in a dimension larger than their actions: the emergent dimension.

I believe that the distinction between building and urbanisation, that is to say the distinction between action by decomposition and composition, also defines the distinction between architecture and urbanism. Architecture intervenes on a rigid structure defined at the beginning of the process, the building, and so runs into very strict economic limits of the scale of this large structure. Urbanism has to deal with the problem of creating large structures out of all of the small scale urbanisations that are undertaken by large numbers of individuals, all seeking to build something to suit their own personal problems. It is in that sense the inverse of architecture. Urbanism takes place in the emergent dimension.

The field of urban design has gained a lot of popularity since efforts to plan whole cities were abandoned. The focus of the urbanists has shifted to the scales considered controllable: the development, greenfield, brownfield and other. The most successful of the urban designers are the New Urbanists. They have managed to produce their name-brand Traditional Neighborhood Developments in practically every city in North America. It starts off inevitably with one developer and centralized ownership of the land that will be urbanised. This land is then decomposed into streets and squares along the principles proclaimed by the New Urbanist charter, the negative of which is decomposed into lots that will be further decomposed into buildings. In terms of production processes, New Urbanist TNDs are no different than the regular, economically-unsustainable subdivisions. They belong in the realm of architecture, and what is worse, they provide no connection to the larger urban context within which they are being inserted, suburbia.

Here is the Mackenzie Towne TND at the limits of Calgary Alberta, in mid-decomposition.

And here we see the development within the larger context of southern Calgary.

What were to happen to the people who have moved into the first part of the development if the developer declared bankruptcy, as has been the case in many developments these recent times? The construction site would remain in perpetuity, and their town would be incomplete. That is the very opposite of what a city is supposed to do, to provide a complete system regardless of the chaotic course of events.

Will the people of Mackenzie Towne live a New Urbanist lifestyle? One look at the bigger scale of the City of Calgary is sufficient to say no. The development is not the relevant scale of the urban life of its inhabitants. This follows from the fact that it is only a small part of the city as a whole, but is also what makes urban design economically possible in the first place. In order to be able to undertake a decomposition at that scale, we must be composing it to a much bigger system of urban relations.

I fear that no matter how intense the efforts the New Urbanists undertake to convert local authorities to their system, they will never be able to transform cities in their emergent dimension. We will continue to see appear, alongside TNDs, gigantic commercial strips, industrial zones and office parks, which will continue to form the emergent dimension of North American cities. At their center will be the caracteristic integrator of all of these urbanisations, the one space that every inhabitant of any modern city shares, the highways.

What then is urbanism? It is the glue that sticks different urbanisations, different architectural projects, together. North America has known only two general types. For all of the 19th century, and the first part of the 20th, the urbanism of North America was The Grid: unending checkerboard patterns of streets between which were blocks that were more or less developable into anything not bigger than the block. As cities grew with more urbanisations, new streets and blocks were composed onto existing streets and blocks, and this went on until the urban chaos became intolerable and people fled to the suburbs, a flight that was enabled by the new urbanism: the highway strip. The highway strip continues to be the compositional rule that integrates all North American cities. If you look again at Mackenzie Towne, the highway that borders it seems to have no relation at all to the development. This amounts to no urbanism. The emergent dimension is empty of any structure.

The New Urbanists have launched a parralel effort, alongside the TND, to reform municipal authorities’ urbanism by inventing a building code, the SmartCode, that is supposed to fit into any city. Building codes have been the primary tool of urbanism for centuries. The reason they worked so well is that they made it possible for the smallest possible urbanisations to create large-scale structures, balancing local adaptation with large-scale solutions in order to create what we today call organic cities. Such a building code can do much to enable complexity, but it must be combined with the creation of the integrator spaces, streets, avenues and highways, that must also grow organically.

Looking over the fact that it doesn’t appear to provide any indication of what to do with highways, the SmartCode ran into the objection that it was rules, and therefore anti-market. Ironically, the market is one of the first rules-based complex systems fully investigated. Adam Smith even christened its emergent dimension with a metaphor that continues to mystify people today: the invisible hand. The invisibility of the market results in many hotly-debated political issues, for example the incomprehension with surging gas prices during hurricanes. The reasons why gas prices should rise so rapidly escape the individual perspective, and angry commuters everywhere demand from politicians that something be done to control things. That attempt at control of the market would have unexpected consequences, just as it does in the emergent dimension of urbanism. Brasilia was the most famous realisation of fully-controlled town planning ever built, but today it is ringed with favelas and functions as one city with them. The emergent dimension of Brasilia escaped the strict control of its planners.

Urbanists must, by the nature of their work, be experts at seeing things in the emergent dimension. The tools to achieve that have yet to be invented. Economic treatises crudely made the case for the economy as an emergent system, but the 200 years of economic history that followed them showed that people would not believe what they could not see. They will not believe in the SmartCode until they can see it either. The invention of the microscope made it possible to see what was too small to see. We must invent the tool that makes it possible to see what is too large to see. Only then can we truly begin to create the cities that we want, as individuals and as communities, without taking a blind leap of faith.

Reference

Sustainable algorithmic design lecture series by Nikos Salingaros.

A demonstration of complexity in New York City

This discussion originally appeared on the Wired New York forums.

Allow me to point to a great example of contemporary emergence in New York City, and perhaps clarify the principles involved.

This, as most of you probably know, is Times Square.

There is a geometry to Times Square that makes it different from the rest of the city, that is to say there is some pattern in Times Square that is shared by every single building and not shared by buildings in the rest of the city. This pattern is the shape of the advertisements.

Those advertisements are not random. There is a complex order to them. The Times Square zoning regulations require that advertisements be placed, in relative (to building floors) proportions, on each facade. This was the result of an intervention by Robert A. M. Stern in the early 90’s. This building code is a localized instruction given to each individual building, that constrains what the owners can do at one scale but gives them total freedom to personalize within that scale and beyond that scale.

The resulting pattern, no matter what advertisements are swapped in for other advertisements, is a place that is immediately recognizable. The code has created an organic symmetry. Should the same code be applied somewhere else in the world, it might be mistaken for Times Square.

Times Square is a system where different individuals, applying the same rule to their own individualized problems, work together without consciously being aware of it to create a large-scale geometric order.

Didn’t Times Square have advertisements beforehand? From the point of view of complexity science, it is irrelevant where the rules that generate complexity came from. It can be from culture. It can be tradition. It can be imposed by government. It can be a multilateral protocol like the Internet. It can be just the physical nature of the thing, like cells that follow their DNA to generate organisms, or it can asserted as abstract logical constructs, like the Wolfram elementary cellular automatons, in which cases there is no will involved in following the rules.

What makes something emergent is this feature: localized decisions unconsciously create large-scale form by following a set of rules shared by other local decisions while solving local problems.

All cities, without exception, are emergent. Even Brasilia has favelas. There is just no way for one single human mind to design at that scale. Even if you were to build a plan for millions of apartments in neat rows of housing complexes, if someone so much as built a shack outside of your sphere of control, the experience of moving from that shack to the housing estate would be emergent. There was never a mortal power, from master builder to god-emperor, capable of avoiding that.

However not all cities are complex, and this is what we generally term an organic city. Complexity means that the city is solving multiple problems at multiple scales concurrently (it is fractal), which means that not only my house and my neighbor’s office are fitted to their task, they are also fitted to their street, their neighborhood, their borough, and the metropolis as a whole. And the street is fitted to its space and the neighborhood, and the neighborhood is fitted to borough, and so on.

As we’ve seen in the past century, a lot of emergent processes are first of all completely accidental, and second complexity-destroying. But even the most boring of suburbia looks “organic” when you zoom out the scale far enough, because at that point it escaped the control of any single individual.

Fake Complexity – CCTV Headquarters

Engineering firm ARUP provided the complexity for this project.

From time to time I happen upon an attempt to “do” complexity that completely misses the point. In this first installment of many “Fake Complexity” topics, the culprit is Rem Koolhaas and his CCTV Headquarters for Beijing.

The choice of Rem Koolhaas is not random. Koolhaas is the only starchitect who understands anything about complexity, making this building that much more tragic. And the sad part is that the CCTV does have some complexity in it – the structural frame of the building is so complex that it had to be generated by computer software, explaining the weird, random shape of the mesh holding it up. The error is that this emergent structure is put to work holding up a horribly corrupt design, and the random pattern of the structure exists to match the similarly random physical stresses the design imposes. The global shape of the building itself is just an aesthetic decision by the architects, it is not the result of a complex process. Complexity only factors in after the architects have done their work. Form here does not follow process.

The fact that the building’s form is not emergent is also the reason why the people of Beijing do not take it seriously as a building. It has already been nicknamed “Big Shorts” by locals, because that’s the form the architects decided for it.

And a comment in passing about the architectural criticism linked above.

You might think that, like a good deal of Koolhaas’s work, the building is as much showmanship as architecture, but it evinces a quiet, monumental grandeur. Some of that is due to the color of the glass, which is a soft gray, almost perfectly echoing the overcast Beijing sky.

What the hell are these people on? Is overcast the new grandeur?

Bonus Fake Complexity Update – Tour Signal by Jean Nouvel

Jean Nouvel was recently announced as the winner of the contest for a second iconic tower in Paris La Défense, which has absolutely nothing to do with him being awarded the Pritzker Prize a few weeks ago. Here is Jean Nouvel’s idea of complexity: a wallpaper of the Mandelbrot Set on the gargantuan atriums of his building. This is an even faker kind of complexity than Koolhaas used, as in that case there was a legitimate emergent process used in the structure of the building. What Jean Nouvel is doing is taking a 2D printout of a complexity-generating computer program and slapping it on the walls of his building. This being kitsch projected to every corner of Paris, it becomes a crime. Thankfully, given the current conditions of global real estate markets, it will meet the same fate as Jean Nouvel’s doomed 90’s project for La Défense, the Tour Sans Fins, and this is why it doesn’t deserve its own Fake Complexity update.

The emergence of a sense of place

Modern urbanism has given us a landscape that many consider to be soulless. Everything looks the same. Nothing creates a sense of place. New Urbanism has attempted to reverse this by returning to traditional architecture and town planning forms. This was done in European new towns, under the advice of well-meaning men like the Krier brothers, in the late 1970’s, and did not succeed. While there are blocks and squares and on-street parking, the general configuration of traditional towns, the new towns did not develop the identity and personal relationships with their inhabitants that was intended with the return to traditional forms. They still experience the same population mobility that the other suburbs of the periphery experience.

The reason this happened is the same reason that New Urbanism has not caught on, despite the fact that everyone agrees with it. The New Urbanists have been focusing on outcome instead of process.

Complexity is an emergent phenomenon. This means that its outcome cannot be determined, that only the process of emergence can be determined, and the outcome must be what results from this process unexpectedly. The sense of place that we seek is not traditional town plans, although those have merits of their own, but the realization of our personalities in buildings.

Home renovation has become the cultural expression of the landed middle classes, and the propagation of the home renovation big box chains is a testament to this culture. I cannot have a single conversation with any middle aged home-owning couple without some renovation project of theirs being mentioned, and I shudder to think how conversations go when they are amongst themselves. I believe that, more than a form of consumer culture or cocooning, this trend is a reaction against the placelessness of suburban environments. As the standardized, tract homes are transformed at small scales by their residents, they come to reflect the choices and personalities of the individuals that inhabit them. This is what had been missing from the speculative, mass-produced housing that colonized the periphery and eventually exploded across the entire landscape. Once buildings have been transformed by someone, the presence of this person is felt in the building’s form. It becomes a unique historical event, and thus forms a place.

How does repetition of identical buildings come to be? The answers are in the building processes. Repetition was never seen prior to the industrial age, and even through the industrial age not all cities actually saw mass-produced housing. American cities laid out on grid patterns all have their share of row buildings, as does London. But in London the trend started with terrace housing for the aristocracy, and other centers of industrial revolution in Europe, such as Paris and Berlin, have no trace of repetition at the scale of working-class neighborhoods in industrial America. The simple fact of industrialization cannot explain this kind of urban morphology. Even today, while the construction of repetitive housing subdivisions continues in the post-industrial world, the industrializing countries such as China are constructing wildly individualized buildings inside the existing urban fabric. And in the informally economic shantycities of Africa and favelas of America, personalized building is the only rule. The latter feel more alive, although less comfortable. That living quality, the result of millions of individual acts of transformation to create fitness, is what gives a place its placeness. But in order for this quality to emerge, there must be a personally-enabling urban process at work.

Christopher Alexander theorized such processes in his Oregon Experiment, where he also wrote a scathing criticism of city plans. He described how the directors of urbanism for the University of Oregon could act to enable the creativity of the inhabitants of the university in the elaboration of new buildings that would solve their personal, individualized problems. This would be the opposite of designing a plan for the university’s expansion that would then be imposed on the inhabitants in perpetuity

The traditionalist New Towns I mentioned do have such plans, and they do forbid personal transformation on the urban fabric. This is why they remain only a product and have not grown into a place. The same fate awaits suburban subdivisions where strict HOA rules forbid changes.

Beyond those two cases, a larger problem still has to be challenged. Why is it that the processes of urbanization in our countries limit or destroy complexity, while enabling it in foreign countries? We must take a critical look at our processes, which are unfortunately often enshrined by government legislation, and replace them with those processes that enable the emergence of complexity. Only then can a new urbanism be achieved.

Placeless:

Regular, oppresive tract homes.

Placefull:

Reference

Alexander, Christopher and others. The Oregon Experiment.

A demonstration of complexity in London

The immensely productive Physicist-Mathematician-Entrepreneur Stephen Wolfram theorized, based on his studies of cellular automatons in the 1980’s, that there exists four classes of physical processes in the universe. Class I is simple continuous behavior (line). Class II is repetitive behavior (checkerboard). Class III is nested, hierarchical-fractal behavior (basic fractals like the Sierpinski triangle). Class IV, the most fascinating, is chaotic behavior (random fractals such as the Mandelbrot Set). Wolfram believes that Class IV behavior, exemplified by the Rule 30 automaton, is behind the complexity we see in the universe, and that very simple generative rules produce it.

The way we as humans are used to doing engineering and to building things, we tend to operate under the constraint that we have to foresee what the things we’re building are going to do. And that means that we’ve ended up being forced to use only a very special set of programs–from a very special corner of the computational universe–that happen always to have simple foreseeable behavior. But the point is that nature is presumably under no such constraint. So that means that there’s nothing wrong with it using something like rule 30–and that way inevitably producing all sorts of complexity.

Wolfram gave this speech on his new science to big shot architecture schools at Yale, Princeton and MIT. He believes that his new science has profound implications for the generation of form in architecture. I agree with him, but not for the reasons he provided. In fact his classification of the geometric properties of different physical phenomenons provides extremely profound insight into the history of architecture, and its future.

A visit to London was what really made me appreciate this insight. London, as an architectural artifact, is quite unique in that its greatest period of growth, the period 1750-1850, coincides with the beginning of modernism in architecture, a time when architecture became in a sense aware of itself and in search of its meaning. Neoclassicism was followed by Gothic Revival, Romanesque Revival, Neo-Venetian, all of it got mixed up in eclecticism, and the invention of new materials and building processes came to confuse things even more. Regardless of stylistic debates, what may be most important about that period is that, for the first time in history, large capital funds for speculative real estate development became available. Where architecture had once been a piecemeal business occurring quite randomly, in London, for the first time ever, housing subdivisions were possible. The result was the terrace housing.

Chelsea South Kensington

The big housing developments in London were initiated by aristocratic landowners who hired architects to plan and control the form their estates would take. Walking through Chelsea and South Kensington, one is faced with sometimes overwhelming repetition of identical houses. Class II behavior, that Wolfram claims is fundamental to engineering, is obviously visible. The architects of the estates, not really knowing the specific constraints of the future residents of the place, opted for endless repetitions of the same building. The fact that each building is a copy of the next, inadapted to the particular wants of its occupants, makes it standard behavior, far from complex.

The human mind is by nature fractal and is repulsed by Class II geometry, which is why traditionally architects have built Class III, hierarchical fractal geometry. This was employed by some terrace builders, such as the architect of the Regent’s Park estate, John Nash. Here the monotony of the model is interrupted by nesting houses in flourishes like arches, or bigger houses with large porticoes.

Cumberland Terrace, Regent’s Park, London

You can see a 19th century panorama of this terrace here.

Classical architectural education, based on the teaching of the classical orders, trained architects in the art of doing such hierarchical decompositions of their buildings. As such most of the high western classical architecture, starting from the renaissance architecture of Alberti (the first modern architect in the sense that his name is more important than any of his buildings, not true of the medieval architects of cathedrals), is rigidly symmetrical. Classically-trained architects only expanded the scales of decomposition as the size of buildings increased, up to the neoclassical skyscrapers that modernists considered to be ridiculous. The classicals were right about the need to create fractal geometry by decomposition of what were rigid engineering plans, what the modernists claimed was ornamental crime, philosophically dishonest and replaced with elementary repetition in their designs (regression to type II geometry). People have hated architects ever since.

Whenever I read through architectural history books, even those of honest traditionalists like David Watkin, I am struck by what is clearly missing from the record. That is to say the towns built up over centuries, the accretion of simple building acts into complex symmetries. The topic is touched by some thinkers of urban morphology, typically under the label of “organic” growth, such as in The City Shaped by Spiro Kostof, but everyone appears dumbfounded by the means through which such symmetry was accomplished. And largely the whole career of Christopher Alexander has been dedicated to decoding this mystery.

Andalusia

But even in the 19th century, when large-scale development was sweeping London, some complex geometry was achieved. These are four distinct buildings on Lincoln’s Inn Fields.

Lincoln’s Inn Fields

We immediately notice that each building is different from the other, having been built for a unique purpose and therefore being a unique solution to a unique problem. Despite that, the buildings form a harmonious geometric composition because they share many transformations to which randomness is applied. Even within one building, Lincoln’s Inn on the left, randomness is visible. The tower is unique, but symmetric with the rest through shared transformations. What we are seeing here is, I believe, a genuine Class IV pattern.

How could this be possible? If Wolfram’s theory on the origins of complexity is correct, then there must be a very simple rule to produce this kind of street scape. This rule can be applied to any random architectural demand and provide a perfectly appropriate solution to an individual problem while remaining completely harmonious with other such random solutions in its neighborhood! Since such organic complexity appears in all human civilizations, then we must conclude that every single building culture in the world has known, at some point, such a rule, and has applied it to solve building problems of all forms. Without understanding how these rules created complexity, they simply repeated them after each successful building.

What to do with new technology? New technology necessarily creates a new scale into the rule, but the remaining rules are still valid. This is visible in the glass structure appended to the Royal Opera House.

Royal Opera House

We can see many shared patterns between the central structure and rightward structure, but not with the new addition on the left. Typical of modernist architecture, the left building is only made of elementary geometry, barely even qualifying it as a Class II structure. It doesn’t feel as though it belongs there at all. There is an important lesson here, one that architects I fear do not want to learn.

Wolfram claims that complexity science is about finding simple rules that can generate complexity. We can decode simple rules from traditional architecture that, even with the modest means of poor villagers, will generate complexity when applied repeatedly to random events, creating random fractals while simultaneously solving a vast diversity of unique problems. This is exactly the kind of work that good urbanists should be doing today, and from there we could allow maximum diversity in our cities without breaking symmetry and harmony at costs as low as the meanest buildings currently cost. If Wolfram is correct, then the rules may be so simple that they may be easily codified into building regulation even by the dullest bureaucrats. Then again the behavior may be so complex (that is to say there is emergence) that no a posteriori codification is even impossible, and the processes by which cities are governed may have to be completely reconsidered. Either way this is not good news for architects. If architecture is so easy, then their idiosyncratic designs are not necessary nor valuable. The big shot schools of architecture that Wolfram visited will be made irrelevant by Wolfram.
References:

Mathieu Helie – Complex geometry and structured chaos
Stephen Wolfram – The Generation of Form in A New Kind of Science
Christopher Alexander – The Process of Creating Life

Emerging the city

In the 20th century, the modern movement in architecture drew up grand plans to remake cities for the machine age. Le Corbusier, the leader of the movement, conceived his Radiant City plan. He designed every part of it himself so that it would work as he had willed it to. His machine provided the solution to four problems: inhabitation, work, recreation, circulation. Everything else was removed.

The idea of a machine city expressed three assumptions that led to the catastrophic results of modernism.

The first assumption is that the city is a machine that solves a problem. It can then be designed as a tool would be.

The second assumption is that the will of a designer can be imposed at the scale of a city.

The third assumption is that the form of a city, its morphology, can be conceived in advance of its development (“planned”).

After a titanic fight over the future of New York City, Jane Jacobs explained this error in the final chapter of Death and Life of Great American Cities. The “kind of problem a city is” shares nothing with the physical and engineering sciences. It is like the biological sciences, a problem of organized complexity.

The city does not solve a problem or some problems, it provides the environment to solve the infinite diversity of little problems that human beings have.

It is so complex that no single human can ever hope to understand it entirely.

Its morphology must be defined by its growth process as it adapts to changes in human needs and desires.

The city cannot have a designer. It cannot be built according to a description fine-tuned to perfection. This has become obvious to practically everyone, although urbanism in the english-speaking world is still tied down by the title “urban planner” in the face of all the evidence that planning makes no difference whatsoever. Still the practice of large scale zoning and site planning continues.

The problem was the absence of an alternative theory.

Today this theory exists. Research into DNA and cellular automata has shown how systems of transformations, as opposed to descriptions, create complexity in nature through emergence. Cells which multiply themselves and interact following simple sets of transformation rules produce forms of astonishing complexity.

A system of transformations is similar to a recipe. It is a list of actions that you must take, as compared to a descriptive system which gives you a picture of a finished object. Imagine trying to bake a chocolate cake with nothing but a picture. Now try again with no picture but a full recipe. By following the recipe, you will get a tasty cake no matter what mold or size of cake you made. If you make a mistake in the recipe, your cake will not succeed.

The definition of emergence is thus: it is a form obtained as a result of following certain processes. The opposite of emergence is design: it is a form conceived by a designer which will be used as a blueprint for its realization.

In emergence, form is the result. In design, form is the starting point.

The 21st century paradigm of urbanism is discovering and applying the right recipe, DNA, transformation set, to build a city, at any size, shape, or starting point, so that it will always work, always be adapted, and always be full of life.