中国进入后城市时代？对规划者的挑战

约翰·弗里德曼【美】 沈 璐 译

Introduction

I imagine that many of you here today are surprised by the first part of the title for my talk∶ “Is China moving into a post-urban era?” All around us we see nothing that couldn’t be called urban, from sky scrapers to airports to high-speed rail networks.Moreover, I have to confess that I am not completely certain that even this term—posturban—conveys the absolute novelty of what I perceive to be happening, and not only in China but to some extent on every continent.Collectively, humanity is creating a new type of human habitat which, although its origins are what we still understand to be the classical city—in my case, say, the Vienna where I was born 87 years ago—a city that could still be viewed as a whole from a given vantage point. The urban habitat has grown and physically expanded to such gigantic dimensions that the only way to see it as a single entity is when it is mapped in twodimensional space or from a satellite high above the Earth. For you who are here today,the image of what I’m calling the classical city may well be some other place altogether,perhaps Republican-era Chengdu. The point,however, is that the dimensions of the urban today far exceed those of past ages and present us with unprecedented challenges,which, if we are completely honest, we don’t really know how to respond to. A group at Harvard’s Graduate School of Design has an ongoing research program under Professor Neil Brenner on what they call “planetary urbanization” where they investigate not only the densely populated parts of our planet but also the reach of the urban into its most distant, extreme outposts∶ the two arctic regions, the Gobi desert, the Sahara, the Himalayas, and even the stratosphere.

The British historian Arnold Toynbee believed that history can be told as a story of challenge and response. While this is surely not the whole story, Toynbee’s theory of history is appealing to me as a planner,precisely because it emphasizes a response that can be creative, and every creative action is already a new beginning. We don’t often completely succeed in the urban projects we imagine, but even failures can be instructive. At its best, planning is a process of continuous social learning.

Social learning takes place when we begin to understand the true nature and extent of the challenges before us. Part of the problem, here, is to find an appropriate conceptual language that will afford us insight into the new phenomena that challenge us to engage with new ways of thinking and acting. That is why I have chosen the term“post-urban,” just as we speak of post-Fordist or post-modern eras. All these formulations suggest a transition from a point in the past to a not yet clearly articulated future. The urban is all around us but, compared to older ways of thinking about cities—cities we could still criss-cross from one end to the other on a morning’s walk—its multiple meanings are different. Although the concept of posturban still subsumes the familiar “urban,” it also points beyond it in ways that I will try to explain in the course of my talk. In what follows, I will therefore employ a conceptual language that, for the most part, will be new to you∶ I’ll be pouring new wine into new bottles, not the old, when I use terms such as“urban super-organism” , the “periurban,” the“fusion of urban horizons,”“self-organizing systems,” and the “noösphere or sphere of the mind,” access to which creates a “public sphere.”

My talk is organized into three parts,each part posing a question. First, what exactly do I mean by a post-urban era?Second, what are the unique characteristics of an urban super-organism? And third,what are the major challenges that call for planners’ creative response to the posturban, particularly in China?

What do I mean by “post-urban”?

At the time of the founding of the People ’s Republic, China’s level of urbanization was on the order of 10 percent;the remaining 90 percent lived in the countryside and worked primarily as farmers,and what they produced was mainly for selfconsumption. Sixty years later, China’s urban population, now roughly estimated at 650 million, has already passed the 50 percent mark, while Chinese farmers, now greatly diminished in numbers, actually produce a surplus that for the most part is now consumed in the new urban areas. Clearly,the country is on the way to becoming completely urban. But these hundreds of millions of urbanites are not distributed evenly across the vast distances of China.The eastern provinces, for example, are more urban than the western, and so on.Moreover, the criterion of who is counted as urban is an administrative one, the hukou registration card, rather than a sociological,cultural, or some other criterion. But surely there are other ways of becoming urban,such as by adopting certain ways of living or engaging in non-farm work. By a more ample criterion such as these terms suggest,some regions, such as the Yangtze Delta,are already completely urbanized. And so you could ask me∶ what do you mean when you speak of a post-urban era? What comes after the urban? And how does this help us to understand what is actually happening.

Let me begin with a formal definition. By a “post-urban” era I have in mind a period of transition during which many single-centered urban regions are gradually absorbed by and incorporated into a polycentric urban system that extends over a relatively compact,densely populated area and is home to multiple millions, as many as upwards of 50 million or more. Such a region can no longer be called a city in any conventional sense;it is an unprecedented form of the human habitat.

Initially, each urban center within such a system was surrounded by periurban zones that themselves were under pressure to urbanize, as the central city extended outwards into surrounding spaces,transforming what were once rural villages into what some called suburban, that is,wholly urbanized places in the outskirts of large cities. At the same time, any agricultural production remaining in the interstices of rapidly urbanizing periurban zones tends to become increasingly commercialized,capital-intensive, and in effect industrialized.To speak succinctly, in the vicinity of urban centers even farming is evolving into an urban type activity. And because of the relatively short time-distances among the major urban centers of a polycentric region,neighboring periurban areas begin to interpenetrate, forming a continuous urban skein. I refer to this process as a fusion of urban horizons.

The periurban is a seemingly chaotic,post-urban landscape of mixed uses that, as a whole, are relatively unplanned. Villages are urbanized in situ but are nevertheless connected to an infrastructural grid that crosses the landscape and links local centers to each other and the world. Being for the most part transacted electronically, these linkages are all but invisible, while other links appear to the eye as vehicular flows of trucks and automobiles. And as dense networks of high-speed transport and communication are constructed, the space-time distances of such a vast new “assemblage” of the urban shrink and enable it to function as a single urban system cutting across multiple jurisdictions. Such an assemblage is no longer what we conventionally understand as a city, even though, like a city, it behaves in many respects as a single socio-economic spatial entity.

The existence of such an entity was discovered as early as 1961 by the French geographer, Jean Gottmann, when he identified the eastern seaboard in the United States as a continuously urbanized area which he named megalopolis. Gottmann,however, pointed to it as only a spatial phenomenon, although he did understand this pluricentered linear system to function in some ways as a single urban system of some 700 km in length. Today’s population of Gottmann’s megalopolis in the eastern United States is estimated to be around 50 million.

Today, a number of such “post-urban”systems can be found in western Europe,North America, Brazil, and of course Asia.To distinguish them from Gottmann’s construct and rethink them from a planning perspective, I will speak of them as Urban Super-Organisms (or USOs)—a term originally borrowed from evolutionary biology.USOs stand for a distinctive form of the human habitat. In China, the most evolved USOs include the Yangtze River Delta from Nanjing to Shanghai, including Hangzhou and Ningbo, and the Pearl River Delta extending from Guangzhou to Shenzhen and across to Hong Kong, Macao and Zhuhai.Elsewhere in Asia, one could perhaps also point to the Tokaido USO extending from Tokyo to Osaka and incipient USOs in South Korea (Seoul), northwestern Java (Jakarta metro-region), and India, for example the emerging post-urban region centered on Mumbai, as well as many other USOs in the making.

I avoid attaching population figures to these “post-urban” regions because the numbers depend on how one precisely delimits them and whether one counts the so-called temporary population of migrant workers and their families as part of the system or not. This is a matter for future research. As far as concerns the two Chinese regions I have mentioned, we can argue that whatever the numbers turn out to be, they will almost certainly continue to increase over the next 20 years, the goal of the new government in Beijing being to urbanize another 350 million rural people. The Yangtze and Pearl River Deltas will thus become a great deal more densely populated by any measure of settlement, including continued in-migration from less urbanized parts in China, natural demographic increase,new communication and transportation infrastructures, and, above all, the changeover from a predominantly export to a more domestically-oriented market economy. The effect of this last source of densification is that it is likely to lead to a much thicker network of inter-industry relations along with a huge expansion of related business services.

①See Nikos A. Salingaros,“ Development of the Urban Superorganism,” Kataraxis #3 (2004) accessed June 8, 2013 at www.kataraxis3.com/Salingaros-Urban_Superorganism.htmSalingaros teaches in the Department of Applied Mathematics at the University of Texas, San Antonio, Texas, and is closely associated with the work of Christopher Alexander.

What are some characteristics of USOs?

As I mentioned earlier, the new sociospatial phenomenon of an urban superorganism (USO—and let me repeat that I believe Shanghai to be a leading part of one, its “dragon head”—is not merely unprecedented in human history and vastly understudied, but must also be described in ways that depart from traditional urban sociology and geography. I will confine myself to only two observations. The first relates to a new dimension of any USO, which has to be understood not only as a physical artifact in three dimensional space but additionally as a densely patterned, dynamic socio-cultural,economic, and political set of interdependent systems that are constituted of tens of millions of interactive decision-making units,including individuals, households, economic,and political and administrative units that are not necessarily aligned hierarchically but connected in various ways to each other via a fourth dimension of face-to-face and electronically mediated communications and exchanges across different scales. The second characteristic, I will argue, is that any USO is to an extent a self-organizing system. I will now turn to each of these in turn. (A third critical characteristic relates to questions of governance. As USOs evolve,becoming increasingly larger until they finally converge upon a vast pluricentered urban entity by way of a fusion of urban horizons,new forms of governance are required, at different scales, that will lead to new relations of decision-making power. But the topic of governance is so huge that I will not be able to do it justice in this relatively brief,introductory comment).

I begin with communication and exchange. This dimension is made possible by a variety of high-speed and ultra-highspeed technologies that allow almost instantaneous communications among virtually all decision-making units both within the USO and beyond it. On the ground, highspeed trains and relatively uncongested freeways make possible face-to-face encounters within normal commuting timedistances of 20 to 40 minutes. In addition,cyberspace allows access to a vast sphere of virtually unlimited information and connection which, as early as 1922, the philosopher Teilhard de Chardin called the noösphere or sphere of human thought (from the Greek word nous, here translated as “mind”) or more broadly, the sphere of self-reflective human communication that extends like a silken skein across the planet.

From a planning perspective, this sphere, so promising in some respects of human progress, has nevertheless serious limitations. If we accept that knowledge should serve as a guide to action—which is a basic premise of planning—the sphere of communication and exchange forces decision-making to become more incremental, more focused, more strategic.Contrary to traditional planning rhetoric,knowledge for decision-making is always fragmentary and drawn from mostly(historical) information about the past. But under conditions of rapid change, as is the case of post-urban China, the past must be judged as an imperfect guide—imperfect for a variety of reasons such as out-of-date and incomplete information at the necessary scale, incorrect interpretations of the available information, huge gaps in research,the mistrust of political decision-makers of even “scientific” knowledge, and so on.Instead, decision-makers are tempted to act in spite of the inherently large uncertainties and risks inherent in bold actions, never sure that resulting outcomes will conform to their optimistic expectations. From a holistic perspective, the noösphere—the sphere of self-reflective thought--may appear chaotic to some, but it is actually helping to give shape to complex new patterns in the material world, as millions of actors incrementally adjust their decisions according to errorcorrecting feedback and other information.Given enough time, however, incremental decision-making has the potential to also become system-transforming though not always in the ways we intend. And when we confront the future as planners, it is the metaphor of social learning that paradoxically reminds us of the limits of even the most expert knowledge.

What I have sketched here is actually the outlines of a partially self-organizing human system that conforms to given parametric constraints that are themselves undergoing constant revision, extensions,and contractions. An urban super-organism can thus be understood as a high-density,four-dimensional spatial system where a change originating at any point tends to ripple through the system, producing unanticipated changes, both small and large,at many other points. A stable equilibrium in such a system is scarcely ever reached,and the system remains in constant motion,as it adapts and transforms itself. There are, of course, laws and customary rules to which systemic change should conform,but these rules serve merely to constrain the existing options actors face in making their decisions; they do not determine them.Likewise, there are enabling infrastructures—water, food systems, electricity, transport,communications—that help to shape the physical form of USOs. And always there are the relentless streams of information originating from both inside and outside the USO that local actors must take into account as they ponder what to do next in the pursuit of their own interests. Much of this information tends to be redundant, nor is it always reliable. Furthermore, for information to be converted into knowledge, it needs to interpret. Unfortunately, to the consternation of many, different interpretations result in different scenarios, so that consensual decision-making is relatively rare, if not impossible, at the macro-scale of USOs.One might even speak here of a surfeit of information, except that we are often unable to distinguish information that is valuable from the dross. In any case, we have to be selective in the information we use. In the end, no one, including at the highest levels of government, has a complete and accurate overview of what, at any given moment, is the actual state of the system or any particular part of it, or has a clear idea in what ways the system as a whole is evolving. Habermas has referred to such a situation as unübersichtlich—i.e., lacking in a clear overview or unintelligible, which he believed to be a characteristic of the modern metropolis.

②Incremental mutual adjustment is typical of all economic transactions in a market economy, for example, See the work of Charles Lindblom for an extensive discussion and its relevance for planning.

And yet, you could argue that the USO“works” in the basic pragmatic sense that life somehow goes on, decisions are made, the trains run on time, the economy produces,technical innovations are adopted for good or ill, housing gets built, and so on. The USO,it turns out, appears to be a fairly resilient system despite occasional disruptions,conflict, and even temporary breakdowns.But it is far from being the efficiency machine some imagine it to be. Self-organization is a socio-spatial process that lacks awareness of itself and remains ignorant of the many side effects it produces. These mostly negative effects can have self-destructive, that is entropic, consequences. I need merely to cite the serious deterioration of environmental quality—the air we breathe, the water we drink, the landscapes we delight in—that is one of the well-known casualties of this process. Ultimately unacceptable inequalities in respect to income, housing, health, and educationare another. If the USO is to become a sustainable human habitat—a habitat for living—conscious interventions are needed to deal with these and other serious inefficiencies.

Obviously, this is where planning comes in, but the powers at the disposal of planners are exceedingly limited, even in China with its unitary, hierarchical administrative system.They address only the three dimensions of land and buildings, rarely (if at all) the fourth dimension of communication, and thus of social, cultural, and political organization.In conclusion, then, I would like to address some questions that are occasioned by my belief that we are moving—and not only in China—towards a largely ungovernable post-urban era in which increasingly selforganizing human habitats of enormous size generate huge inefficiencies and other entropic processes that threaten to undermine whatever hopes we may have for continued human flourishing.

In the post-urban era, what challenges do planners face?

The condition I have called post-urban does not at present extend uniformly across all of China. But it is already visible in the Yangtze Delta where 100 million people are living essentially urban lives in a compact area of about 100,000 square kilometers—a third the size of Italy—divided among 22 major cities. On a day-by-day basis, the Delta is thus a region of great complexity;it is tightly woven together economically,physically, socially, and inevitably politically;and its several periurban areas have in effect become fused or nearly so. Such a region,I have argued, is largely self-organized,though not as efficiently as it might be.That is why I have called it an urban superorganism, a new form of the human habitat.What are some of the challenges for the planners of this region which has played such a strategic role in China’s century-old quest to become modern?

I am not here to give advice to planners whose knowledge of this region is infinitely superior to mine. Rather, I want to point out some challenges that a heavily urbanized region such as the Delta present to planners and how they might respond to them. And so I return to the question of complexity which,given the astronomical lines of interrelation among decision-making units in the Delta,we could call a deep complexity that should be humbling to all of us in our desire to correctly guide its future direction.

Planners lack the instrumentalities to control everything that goes on in such a vast and restless urban landscape that is governed less by man-made laws than by the law of incremental mutual adjustment among millions of actors as they react to perturbations in their environment. One of the early scientists of cybernetics, Ross Ashby, formulated the famous “law of requisite variety” which, when generalized,could be stated as follows∶ “the solution to any problem must be as complex as the problem itself.” When this statement is applied to social issues, being short of requisite variety means that scientific knowledge, including planners’ knowledge,is much too simplistic to adequately address the actual complexities being modeled.Scientific knowledge comes to us in the form of models that, of necessity, are a radical simplification of reality. That is both their beauty and power and may help us explain a given phenomenon. But no model can tell us what to do; it lacks requisite variety. In other words, there can be no “master plan” for the USO of the Yangtze Delta.

As planners, we have far too much faith in models and their seductive simplicity.Intuitively, we have looked for other ways of accessing requisite variety by, for example,involving larger and larger numbers of people in the search for best solutions to what are otherwise intractable problems. Let me mention just three of them.

The first is to share information with the relevant public so that each member of that public is better informed and in a better position to reduce the uncertainty and risk of their own actions. This was the secret of success of French national planners in the post-war period of reconstruction in the late 40s and 50s of the last century, when the central government initiated a form of planning which they called “indicative.” The French indicative plan was about intentions only and concerned chiefly new investments,some to be made by the government itself,others by powerful private agents. The indicative plan, which was a relatively shortrange plan, was widely shared among all players in the game in the course of periodic consultations who, in turn, informed each other about their own intentions during the projected period. Adjustments and agreements followed these consultations,the end result of which was a significant lowering of uncertainties about each other’s intentions.

A second way that sharing information has been done to good effect is through participatory planning. This is particularly important at a time such as the present when quality of life issues are coming to the foreground of public policy, and planning shifts from the large-scale to the more intimate spheres of life worlds embedded in the fine grain of urban neighborhoods. When done well—and careful preparation here is essential—its objective is to draw in active members of local communities to respond with their own ideas about the changes that are needed to improve the quality of life in specific localities. Participatory planning of this sort aims at establishing an open dialogue or two-way communication between government and local residents. In a region of 100 million there are thousands of neighborhoods of various sizes, and local people are the best source of information about what needs to be done to improve the quality of local life. A responsive government will take care to listen to these voices and incorporate them in their overall programming.

The emergence of a noösphere in China,which I have already mentioned, creates other opportunities for sharing information.We can now engage people wherever they live through hand-held devices, i-phones,micro-messages and the like whose numbers are exploding. Planners have been slow in taking advantage of these new technologies.As in the case of neighborhoods (which is a kind of spatially defined public), multiple publics are increasingly emerging which,though spatially dispersed, are vitally interested in anything that concerns them,whether it is food security, air and noise pollution, ecological footprints, damage to beloved landscapes, housing needs, sports arenas, health issues, corrupt practices…the list is virtually endless. The knowledge of these dispersed, specialized publics can be drawn upon in the same way as in spatially defined neighborhoods∶ their concerns can be listened to, their active participation in planning can be encouraged.

There is an ancient tradition in China for people to petition the government,complaining of injustices or asking the authorities for help. But today’s technology allows us to go far beyond petitioning. Where response times are virtually instantaneous,as they are now, all kinds of information can flow up from people to the government,instead of only trickling down. For instance,there is a tendency in China to hush up disasters, whether of a train wreck or polluting chemicals in a river system, or the burning of a chicken processing plant in which more than a hundred workers perished.This silencing of what should be news (and thus in the larger public domain) no longer works, as information is instantaneously spread through cyber networks across the country. The government’s fear is of losing people’s confidence, but the silencing of disaster news tends to have just the opposite effect. It makes people angry not to be told of what has happened, not to be able to vent their frustration and to be treated like children. Without critical voices, there can be no social learning, which under rapidly changing circumstances is of the essence of good planning.

Allow me to close with some comments on collaborative planning, especially in periurban areas whose horizons are in a process of fusing into a continuous landscape of the urban. Periurban areas in China come under the direct control of prefecture-level central cities, because they are essential to their functioning. It is from periurban zones that fresh food reaches the city; where new industries and other space-consuming projects grab periurban land for their own use; whose watersheds must be protected and ground water reservoirs carefully managed to prevent them from becoming depleted; where open spaces that are essential for the good health of city dwellers must be set aside as recreational parks;where landfills and solid waste disposal facilities are typically located; and where new housing estates are often located. All these requirements must be fitted into what is an already small and continuously shrinking terrestrial space. Because of the close proximity of urban centers to each other, their respective periurban spaces will eventually join up into a single space that must be shared with neighboring centers, even though such sharing may lead to tension.Conflict can be avoided, however, so long as two or more parties agree to collaborate on land use planning issues across jurisdictional boundaries of the periurban. Until the recent present, each urban center saw itself as competing against all other cities for inbound investment and was reluctant to collaborate on common projects. Hopefully, this is now changing, especially in USOs such as the Yangtze Delta, which is increasingly behaving as a single living entity.

I have avoided dealing with the central issue of governance for USOs, a topic that will obviously require a great deal of cooperation across jurisdictional lines, the whole being larger than its parts. There is a substantial literature in the Englishspeaking world on metropolitan and regional governance, but none of this has much to say that would be useful for China’s USOs.Our traditions of governmentality are too different to be of much help for places like the Yangtze Delta region. So I merely want to place a reminder at the end of this long talk that the issue of regional governance will sooner or later have to be resolved before the entropic forces that are continuously at work in this region—particularly with respect to the environment and various forms of growing social inequality—succeed in gaining the upper hand.

1 从“城市化”到“后城市化”

“中国进入后城市化时代？”很多人会质疑这个假说。的确，在我们的周围，所见所闻所感，无一不是城市化的：摩天大楼、机场、高铁等等。此外，也必须承认，现在还很难确定，“后城市化”这个词最终会有怎样的演绎。但可以肯定的是，新时代已经到来了，不仅仅在中国，在各大洲的不同地方均有迹可循。可以说，人类正在创造一种新型的栖息地，尽管它的起源仍是我们熟知的“传统城市”。以奥地利首都维也纳为例，大约在一个世纪前，当时人们仍能从城西的卡伦堡山上俯瞰城市的全貌。但今天，跟许多大城市一样，只有从卫星影像图上才能辨识城市的边界。今天城市的规模超过了以往任何一个时代，给我们带来前所未有的挑战。哈佛设计研究生院正在进行一项名叫“星球城市化”的研究，研究范围不仅覆盖人口密集的区域，而且把视角伸向我们星球最遥远的深处：两极地区，撒哈拉沙漠，喜马拉雅山，甚至平流层。

英国历史学家阿诺德·汤因比认为，历史是人类面对挑战和应对挑战的故事。尽管这个观点并不全面，汤因比的历史观却揭示了一个这样的事实：作为规划师，响应挑战是创意的体现，每个创造性的行为本身就已经是一个新的开始了。并非所有的城市规划项目都会获得成功，但即使是失败经验也是富有启示意义的。从这个角度上讲，规划是一个不断向社会学习的过程。

当人们从理解事物本质和应对挑战开始，其实就已经开始向社会学习了。为了概括上文描述的新挑战、新思维和新对策，本文选择了“后”这个术语表达相应的概念，正如此前人们创造的“后福特主义”或者“后现代主义”等语汇一样，它们都描述的是从过往的一种确定状态向未来尚未可知状态的过渡。尽管城市无所不在，但与我们以前熟悉的城市相比，现在的城市意义正在变得更加多元。尽管“后城市化”一词的词根是“城市”，但要真正理解其含义，不能“旧瓶装新酒”，而要“新瓶装新酒”，需要对一些新概念进行诠释和理解，如“城市超级有机体”、“城市边缘区”，“聚合城市”、“自组织体系”和“智域或智慧领域”等，而概括以上这一切的则是“公共领域”。

2 “后城市化”的内涵

在新中国成立的时候，全国的城市化水平仅为10%，其余90%的人生活在农村，主要从事农业劳动，农业产出大部分用来自我消费。60年后的今天，中国的城镇人口已达到6 500万人，城镇化率超过50%，农民的数量大大削减，减少部分被城市吸纳，成为城市劳动力。但问题在于，数以百万计的新城镇化居民并非均衡地分布在中国广袤的土地上，比如东部沿海省份较西部内陆省份吸纳了更多的剩余劳动力。此外，现今城镇人口的统计方式仅凭借户口控制的行政手段，而忽略了社会、文化等关键因素。因此，除了户口之外，还因引入生活方式、从事非农工作等方法推进城镇化。长三角地区已经几乎完全城镇化了，因此还需要引入新的概念来帮助人们认识城市化之后的情形。

“后城市化”描述了一个城市（群）构成过程中的过渡时期，从许多单中心的城市区域逐渐被吸纳到一个多中心的城镇化体系内，后者以相对紧凑、人口密度高为特征，其人口甚至可以达到5 000万或更多。这样的城镇化系统很难用传统的城市定义加以概括，是一个前所未有的人类栖息、聚集的形式。

每个核心城市最初都是被乡村包围着的。这些乡村地区时时受到城市化的压力，这种压力源自核心城市向周边扩张的动力，乡村地区被改造成所谓的郊区，是核心城市周边完全城市化的地区。与此同时，任何在这些城市化地区缝隙中残存的农业生产，都很快吸引到资本投资，引入工业生产。简单地说，核心城市周边的哪怕是农场也会最终演变成城市。由于距离和区位优势，城市周边的各郊区组团也开始相互渗透，形成连续的城市连绵区，成为“聚合城市”。

城郊看似混乱、功能混杂，并呈现后城市化的城市景观，整体而言缺乏规划的指引。村庄被就地城市化，但其市政基础设施仍需要接入核心城市的管网，通过核心城市与其他城市相连，进而与世界相连。电子商务时代，联系方式更加数据化了，更加隐形了，但却更加凸显交通联系的重要性。密集和高速交通网络的建成，时空距离的有效缩减，诞生了新的、更加庞大的“城市组合”，并使之像一个城市一样运转，而不考虑行政边界的限制。这种城市组合尽管在很多方面形成了独立的经济社会的空间整体，但我们不能用传统的城市定义去理解它。

早在1961年，法国地理学家简·戈特曼便发现了美国东部沿海城市连绵的现象，并命名为“大都市带”。但戈特曼却认为这只是个空间现象，这个延绵700km长的线形、多中心城市系统会像一个城市一样运作。如今，在美国东部沿海大都市带上已经集聚了近5 000万人口。

如今，世界上已经有很多这样的“后城市”系统，如西欧、北美、巴西，当然还有亚洲。为了区分戈特曼的假说，并对其进行规划角度的反思，我将其命名为“城市超级有机体”。这是一个从生物进化学引入的概念，是一个人类聚居的特殊形式 。在中国最大的两个城市超级有机体是长三角和珠三角，后者还包括香港和澳门。在亚洲的其他区域，较成熟的是日本东海道地区，从东京到大阪；还有尚处于初级阶段的首尔、雅加达和孟买大都市区等。

为尽量避免将人口因素加入“后城市”区域的定义中来，因为人口的界定总是不精确的，比如是否将所谓的外来务工人员及其家属组成的临时人口计入统计范围内，对未来更精确的研究会产生一定的影响。正如上文中提到的两个中国大都市区，不管用何种口径和方法统计人口，它们的人口都将在未来20年持续增长，这也是受到了中央政府的新型城镇化的影响。与此同时，中国正在经历从出口导向向内需导向的经济发展模式转变，在此情况下，城市间的产业和商贸联系会愈加加强，从而形成更加紧密的城市城际联系。

3 “城市超级有机体”的特征

①参见尼科斯A. 萨林加罗斯. 发展城市超级有机体. Kataraxis2004（3）www.kataraxis3.com/Salingaros-Urban_Superorganism.htm（2013.6.8.）。萨林加罗斯任教于得克萨斯大学应用数学系，曾是克里斯托弗·亚历山大的亲密同事。

城市超级有机体（USO）是一个新型的社会空间现象，上海将起到“龙头”的作用，在人类历史上尚属首次，尚处在研究的初级阶段，与传统的城市社会学与地理学有着很大的差异。城市超级有机体有两个主要的特征：一是规模，不仅是三维的物理空间，而且是人口密度高、社会文化、经济和政治活跃的地方，一般来说是一个千万级人口组成的相对独立的体系，包含个人、家庭、经济、政治和行政等单位，形成交互式决策机制。他们不一定形成决策的等级体系，而是通过多种渠道进行沟通，越来越多地通过第四维空间，即以电子信息为媒介，在不同的空间尺度中进行交流和交换。二是自组织的体系，任何一个城市超级有机体都在一定程度上是一个自组织系统。三是“善治”，随着城市超级有机体的发展和演化，最终形成一个巨大的多中心的城市，成为一个聚合式的城市。在这样的情况下，不同尺度上的“善治”就变得很重要了，形成新的决策体系。

随着技术的发展，USO内部和外部的交流的时间间隔变得越来越短，各单位在虚拟空间里的决策几乎是瞬时完成的。除此之外，虚拟空间还提供了无限的信息，以及信息之间相互联系的可能性。早在1922年，法国哲学家德日进就提出了“智域”的概念。这个概念源于希腊语，意思是人类智慧环境，或者更广义的理解是信息流如同丝线般缠绕在地球的表面。

尽管“智域”体现了人类进步，但从规划的角度来看，仍存在诸多局限性。如果我们将知识作为行动的指导，沟通与交流的圈层使得决策变得更加渐进性、更加聚焦和更具战略性。与传统的规划思维不同，我们决策所需的知识通常是碎片化的，而且主要源自于过去的信息。但是，在信息快速交换的条件下，比如在“后城市”时代的中国，过去的信息通常无法提供完美的指导，比如在某些必要的层面存在过时的和不完整的信息，有效的信息被错误解读，研究存在巨大鸿沟，政治决策不可信等。决策者通常冒着巨大不确定性的风险而作出大胆的决策，不管其结果是否达到最优的预期。从整体的视角来看，“智域”实际上能够帮助在现实世界中塑造更加复杂的新模式，成千上万的行动者根据试错的反馈信息渐进式地调整他们的决策。只要时间足够充分，这种渐进式的决策能够促成整个系统的转型，尽管可能不会是我们所意想的那样。对于规划师而言，“向社会学习”提醒我们，当我们面对未来时，就算是拥有最专业的知识也是存在局限的。

这里勾勒的实际上仅仅是人类自组织系统的一部分，是符合给定的约束条件的部分，而这些约束条件本身也是在不断修正、扩展和收缩的。因此，城市超级有机体可视作高密度的四维空间，任何一点上的变化都会在整个系统波及系统的每个部分，产生或大或小的变化，系统几乎从未达到过平衡，而是一直处于持久的动态中，不断去适应和转变。

当然，有一些规则和原则约束上述的转变，然而，规则只是指导人们如何对现状问题作出选择，并不起到决定性作用。同样，城市超级有机体所需要的基础设施，如水、食物、电力、交通、通讯等，人们往往可以从城市超级有机体的外部和内部两方面获取信息，但仍需要通过目标导向和利益导向来甄别信息的价值。信息往往是多余的，同时也是不可靠的。其次，信息变为知识是需要理解的过程。

不幸的是，在很多情况下，不同的愿景条件下对信息的解释是不同的，因此，在城市超级有机体的宏观层面上，意见统一的决策结果一般是很少见的，甚至是不可能的。信息过量会使人们很难分辨信息的价值。无论如何，规划师必须有选择性地使用信息，包括政府最高层在内的所有人，对于系统的即时动态、特别是系统的部分特征，以及系统运转机制等，有一个全面和准确的概念，哈贝马斯称之为“迷茫”，也就是说缺乏一个明确的概念，这也是他对现代化大都市特点的普遍认识。

人们可能会认为，一般意义上来看，城市超级有机体还是运转正常的：无论如何生活在继续、决策依然可以做出、火车运行准点、经济依旧运转、技术革新无论好坏依然进行、住宅还是在不断建设等等。似乎城市超级有机体是一个弹性很大的系统，尽管它有时也会偶尔出现故障。但事实上，它远非人们想象中的“高效的机器”。自组织是一个社会空间过程，缺乏对自身的认识，也会忽视其产生的副作用。大多数的负面影响是有着自我毁灭的严重后果的。我只需要举出自然环境的例子：我们呼吸的空气，我们喝的水，我们欣赏的风景，这些都是负面影响的受害者。最终还影响到收入、居住、健康和教育等方面的不平等。如果城市超级有机体要成为可持续的人类栖息地，就必须对上述提到的（但不限于）非有效部分进行干预。

显然，规划可以在这方面有很大的作为。但规划师的权利极其有限，即使在中国这个自上而下集中管理式的国家。规划师习惯于三维的思考方式，无论是对土地还是建筑，很少对第四维空间的信息领域进行思索，包括社会、文化和政治体制等方面。总之，我再次回到前文提到的观点，我们正在迈向一个难以治理的后城市时代，而且这不仅是在中国。不断增长的自组织力量产生巨大的低效，对我们所希望看到的人类持续繁荣产生威胁。

4 上海“后城市”时期的规划应对

在中国，后城市化的发展并不均衡。但在长三角地区，超过1亿人生活在10万km2的土地上，区域拥有22个大城市。根据上文的定义描述，后城市化的趋势在这里已经十分明显了。从日常需求来看，区域已成为复合的整体，在经济上、物理空间上、社会结构上，未来甚至无可避免在政治方面，都紧紧地交织在一起。这样的一个城市区域组织方式，很大程度上源自“自组织系统”，尽管这不一定是最有效率的组织方式。因此，城市的超级有机体是一种人类集聚的新形式，那么城市规划会面对哪些挑战呢？

在面对这样一个庞大和焦灼的城市环境时，规划师缺乏控制一切的工具。相较于人为制定的法律的影响，我们的生存环境更多地受到数以百万的参与者的增量相互调整来应对环境扰动所产生的影响 。控制论奠基者之一的罗斯·阿什比教授提出了著名的“所需多样性原则”，概括起来可以认为：任何问题的解决方案必须跟问题一样复杂。当这个原则用于社会学时，任何一种单一学科（包括规划学在内）、任何一种单一模型对于复杂问题来说都过于简单。科学的力量在于抽象现实，将自然现象和社会现象归纳成模型、模式和模块，是对现实世界的高度概括。但没有一种模型能告诉我们未来该怎么做。换句话说，长三角的城市超级有机体是不可能用总体规划进行控制的。

作为规划师，我们对模型有着太多的信心，对抽象化问题有着太多的眷恋。直观地来说，我们通过一些其他方法来探究所需多样性，主要有以下3条路径：

第一个方法是让利益相关方的每个成员都更好地获取信息，来降低行为的风险和不确定性。比较成功的例子是上世纪40年代末和50年代，法国中央政府在战后重建的过程中引入的“指示性规划”，将注意力放在新的投资方面，包括政府投资和大开发商的投资。当然，指示性规划的周期尽管比较短，但在项目过程中，所有利益相关方在国家规划师的组织下进行定期的磋商，对规划和建设进行调整和决议，增加了政府、开发商和民众之间的理解，从而降低了项目开发的不确定性和风险。

第二个办法是通过参与性规划来达到信息共享的目的。参与性规划在涉及民众生活质量的公共政策制定中显得尤为重要，尤其是当规划从宏观层面进入与生活空间有关的社区规划时。参与性规划的主要目标是吸引当地社区的活跃成员，回应他们对于社区生活改善的具体要求。这种类型的规划是要在当地政府和市民之间建立一个双向的、开放的交流平台。在一个千万人口的区域，有数以千计的各种规模的社区，当地的居民是改善当地的生活质量的信息的最佳来源。一个对人民负责的政府有义务去聆听这种声音，并将这些建议整合到规划当中去。

中国“智域”的出现，为信息共享创造更多的机会。我们现在能够通过手持设备、iphone、微信等工具将更多的人纳入其中。规划师在利用这些新技术方面有点滞后。比如说在邻里空间中，多种类型的分散式公共空间开始呈现，开始对于他们相关的任何事情都感兴趣，比如食品安全、空气污染、生态足迹、景观破坏、住房需求、体育场馆、健康问题、腐败行为等。这些分散式的专业公共领域的知识可以与邻里空间一样被采用。我们需要倾听他们所关注的，而且需要鼓励他们积极参与到规划中。

在中国，上访已经有很悠久的历史了，民众对不公正的抱怨或请求当局提供帮助。但是今天的技术进步能够让我们做得更多。如今，所有的信息都能由人民自下而上传递到政府，从而改变了过去自上而下的传递方式。例如，中国通常对灾难事件保持沉默，如火车事故、化工厂污染、工厂失火等。在互联网时代，这种沉默不再有用，信息很快会传播到全国各地。政府可能担忧人民失去信心，但是对灾难事件的沉默只会取得相反的效果。人民会恼怒没有被告知而无法宣泄沮丧与被戏耍玩弄。如果缺少批判的声音，也就没有社会化学习。而在快速变化的环境中，这种社会化学习对于好的规划是至关重要的。

最后，想评论合作式规划，特别是在那些正在经历城市化过程的城市边缘区。中国的城市边缘区受中心城市管辖，因为他们对于中心城市的功能非常重要。比如，为城市提供新鲜食物，为新产业与其他大项目提供土地，流域被保护，蓄水池被保护，为城市居民提供开放休闲空间，生活垃圾、废水处理，新的房产建设等。所有这些需求都将被安置在越来越狭小与不断收缩的空间。由于与城市中心非常接近，不同城市中心的城市边缘区最终会接合为统一的空间，被邻近的城市中心所共享。尽管这种共享会导致紧张，但是如果各方能够对跨行政边界的土地利用规划的合作达成共识，这种矛盾就能够避免。当前，每个城市中心都在为吸引投资而与其他城市竞争，不愿进行项目合作。我希望这种状况能够改变，特别是在像长三角地区的城市超级有机体中，这些区域越来越像一个单一的整体。

在此没有谈论城市超级有机体的治理问题，治理要求跨行政边界的大规模合作，达到整体大于部分的效果。国外有很多关于大都市区和区域治理的文献，但是这些文献对于中国的城市超级有机体来说作用不大。因为国外的治理传统与中国非常不同，因此难以帮助长三角地区。所以，我只想提醒一下，只要区域中的系统熵力，特别是关于环境和各种不断增长的社会不均衡形成的熵力，持续地起作用并占据优势，区域治理问题迟早能够解决。

（本文以约翰·弗里德曼教授于2013年7月8日在上海市规划和国土资源管理局举办的“大师讲坛”上的报告为基础，进行翻译、整理和编辑，以飨读者。）