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Complexity, Cognition and the City aims at a deeper understanding of urbanism, while invoking, on an equal footing, the contributions both the hard and soft sciences have made, and are still making, when grappling with the many issues and facets of regional planning and dynamics. In this work, the author goes beyond merely seeing the city as a self-organized, emerging pattern of some collective interaction between many stylized urban "agents" – he makes the crucial step of attributing cognition to his agents and thus raises, for the first time, the question on how to deal with a complex system composed of many interacting complex agents in clearly defined settings. Accordingly, the author eventually addresses issues of practical relevance for urban planners and decision makers.

The book unfolds its message in a largely nontechnical manner, so as to provide a broad interdisciplinary readership with insights, ideas, and other stimuli to encourage further research – with the twofold aim of further pushing back the boundaries of complexity science and emphasizing the all-important interrelation of hard and soft sciences in recognizing the cognitive sciences as another necessary ingredient for meaningful urban studies.

Inhaltsverzeichnis

Frontmatter

0. Introduction

Abstract
As the title testifies, this book suggests a conjunction between three components: Complexity, Cognition and the City. The first two – complexity theory and cognitive science – refer to relatively young scientific domains, while the third – the city – is an old, or rather ancient, entity and artifact.
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THE CULTURES OF CITIES

Chapter 1. The Two Cultures of Cities

Abstract
One of the most famous observations in the history of science is Snow’s thesis about The Two Cultures – the culture of the sciences and scientists and the culture of the arts, humanities and the “literary intellectuals” as Snow referred to the proponents of this second culture. According to Snow the breakdown of communication between the “two cultures” is a major hindrance to solving the world’s problems. C. P. Snow – a British scientist and novelist – delivered this thesis on May 7, 1959, as the Rade Lecture in the Senate House, at the University of Cambridge, England. The thesis was reformulated and extended by him a few years later in his The Two Cultures and a Second Look (Snow 1964). “It is hard to see”, writes Yee in a review to a 1993 new addition of Snow’s The Two Cultures, “why quite such a fuss was made over Snow’s lecture at the time; as he himself was the first to admit … [that] nothing he said was particularly original” (Yee 1993).
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Chapter 2. The First Culture of Cities

Abstract
The quantitative revolution was an attempt made in the 1950s by a new generation of urbanists to transform the “soft” descriptive study of cities into a “hard” analytical science (Burton 1963). These urbanists have revolutionized the field mainly by adopting location theory – a group of theories developed since the mid-19th century, mainly by economists who added space into the otherwise ‘spaceless’ economic models, and settlement geographers who employed economic consideration and physical analogies as means to explaining settlement patterns. The “founding father” of location theory and by implication of the quantitative revolution, was the 19th century German economist Johann Heinrich von Thünen with his Isolated State and our story begins with him. I write “founding father” in brackets because economist Thünen will never know that some 120 years after publishing his Isolated State, his work has become the foundation for a new theory of cities and settlements.
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Chapter 3. The Second Culture of Cities

Abstract
In the early 1970s we see a rather unusual development in the domain of urban studies: Some of the leading urbanists of the quantitative-positivistic “conviction” that dominated the discipline in the 1950s and 1960s started to question the scientific and social validity of their own project. The most prominent among them was David Harvey (1973) with his Social Justice and the City – a book that produced the most influential critique to date of positivist urban studies, that is to say, of the first culture of cities. Harvey’s attack came from a Marxist-Structuralist standpoint. Others attacked positivistic geography and urbanism from phenomenological and idealistic positions that later came under the title of humanistic geography. Together these two lines of criticism formed what I’ll refer to below as SMH (Structuralist-Marxist and Humanistic) urban studies. Sect. 3.2 surveys the field of SMH urban studies.
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Chapter 4. Complexity Theories of Cities (CTC)

Abstract
Henri Bénard, a French physicist working at the beginning of the 20th century, found the following about a liquid in a round vessel heated from below: At the beginning of the process, when the temperature difference between the heated bottom and the cool top is low, the heat is being transferred by conduction and no macro-motion can be observed in the liquid. However, as the temperature difference increases and a certain threshold is reached, the movement in the liquid becomes instable, chaotic and then a strikingly ordered pattern appears: The molecules of the liquid which at the beginning were moving in random, suddenly exhibit a coherent macro-movement in roles which are millions of times larger than the molecules. As can be seen in Fig. 4.1, the motion of the roles forms a hexagonal pattern on the surface of the liquid. This pattern is in fact an outcome of the movement of the hot liquid, which rises through the center of the honeycomb cells, and of the cooler liquid, which falls along their walls. All this happens as if by an external force. Yet no such force exists – the spatial order appears spontaneously, by means of self-organization.
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Chapter 5. Complexity Theories of Cities Have Come of Age: Achievements, Criticism, and Potentials

Abstract
Complexity theories of cities (CTC) have come of age. What some two and a half decades ago was a narrow stream of studies – written mainly by physicists applying theories from physics – has now become not a flood but an established interdisciplinary research domain engaging urban geographers, planners, urban designers, regional scientists, mathematicians, physicists and others. In addition to the constant flow of articles, we start to see attempts at integration in the form of spatial theme issues (Environment and Planning A, 2006) and of books (Pumain 2006; Benenson and Torrens 2004; Allen (1997), Portugali 2000, 2006; Batty 2005). In such attempts at integration it is just natural to find appraisals of what has been achieved by CTC in the last two decades and a half.
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COMPLEXITY, COGNITION AND THE CITY

Chapter 6. Cognition, Complexity and the City

Abstract
One of the main conclusions from the previous chapter is the need for “a cognitive approach to urban dynamics”; more specifically, the need to add to CTC an explicit consideration of the cognitive dimension of cities and urban agents’ behavior as developed in cognitive science. Several preliminary and preparatory steps toward this aim were made in previous papers (Portugali 2000, 2004, 2006a). Part II of this book that we now open attempts to integrate the previous studies and to provide a more comprehensive view on Complexity, Cognition and the City; the present chapter can be seen as an introduction to Part II. The discussion below develops by binding together the three elements of this project: cognition, the city and complexity. It starts with a concise introduction to cognition and cognitive science (Sect. 6.1). It then looks at the relations between cognition and the city (Sect. 6.2); next, at the relations between cognition and complexity (Sect. 6.3) and finally, at the implications thereof to the relations between cognition, complexity, and the city (Sect. 6.4).
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Chapter 7. SIRN – Synergetic Inter-Representation Networks

Abstract
SIRN (synergetic inter-representation networks) was originally developed by Haken and myself as an approach to cognition and cognitive mapping that integrates two notions: IRN (inter-representation network) and synergetics. We have elaborated SIRN is two steps. In the first step we have elaborated a general SIRN theory and model; in the second step we have derived from the general model three submodels that refer to the way the interacting network of internal and external representations is related to the cognition and (spatial) behavior of, firstly, a single person (the intra-personal submodel), secondly, several persons acting sequentially (the inter-personal submodel) and finally, many persons acting simultaneously (the interpersonal with a common reservoir submodel). As we shall see below in some detail, the canonical case study for the latter submodel is the city game with the implication that SIRN is, in fact, a cognitive theory of urban dynamics.
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Chapter 8. Shannonian Information and the City

Abstract
The question of ‘what it is in the externally represented face of the city that makes it imaginable’ was one of the two pillars upon which the domain of cognitive mapping was founded (Chap. 6). The other pillar concerned the nature of internal representation, in the case of cities – of the image of the city. Lynch’s (1960) The Image of the City as we’ve seen above (Chap. 6) was an attempt to answer the first of the two questions. Today, five decades later, Lynch’s work is still the authoritative response to this question. How is that possible? One reason is the ingenuity and abundant intuition that typifies Lynch’s study. Another reason, however, is the fact that there has been relatively little research on that issue since the appearance of Lynch’s book. Following mainstream cognitive science most students of environmental and urban cognition have focused their research efforts on the nature of internal representations such as cognitive maps, putting aside the very face of the city as uninteresting or irrelevant.
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Chapter 9. Semantic Information and the City

Abstract
This chapter should be seen as “Part Two” of the discussion on information theory in the previous chapter. In both chapters we discuss Shannonian and semantic information and as we’ll see immediately, these two kinds of information are interdependent. However, while in Chap. 8 the emphasis was on Shannonian information and the city, here the emphasis is on semantic information and the city. The discussion below starts by showing the way these two notions of information are interdependent (Sect. 9.2). Next, Sect. 9.3 looks at several processes that are associated with semantic information, namely, at pattern recognition, grouping, categorization and self-organization. Section 9.4 that forms the core of the whole chapter examines the implications to information theory, cognition, pragmatic information, urban elements, SIRN and the notion of information adaptation. Finally, the concluding chapter looks at what has been achieved and indicates future research directions.
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Chapter 10. Notes on the Category ‘City’

Abstract
Cities are huge artifacts – among the largest artifacts ever produced by humans. Each city is also an environment – an artificial environment (see next chapter). For about half the world’s population, the city is the environment within which they live, act and behave. Through their action and behavior, people constantly reproduce and change that environment. The city is also a category – a cognitive construct in the mind of people that refers to the many city instances that exist in the world.
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Chapter 11. Complex Artificial Environments

Abstract
As we have seen above, complexity theories have developed in the sciences and with respect to natural phenomena and then at a later stage were applied to cities. We have further seen that the various applications to cities are based on analogies that can be made between natural phenomena and processes and urban phenomena and processes. But the validity of these analogies is only partial as cities are not natural entities; they differ from the latter in a fundamental twofold respect: first, each city is an artifact. Second, the parts of cities and of similar artificial systems at large, cannot be likened to the atoms and molecules of the Bénard experiment, not to light waves in the LASER, nor to the sand grains of self-organized criticality: each has mind, brain, memory, aims, plans and each is acting and behaving as a result of these aims in an unpredictable way; in short, each of the parts of cities is itself a complex self-organizing system.
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COMPLEXITY, COGNITION AND PLANNING

Chapter 12. The Two Cultures of Planning

Abstract
Cities and planning are intimately related; so much so that the notion ‘planning’ is commonly employed as shorthand to the more longer term ‘urban and regional planning’ (which is not the case with economic or social planning, for instance). A possible reason for this is that cities were always regarded as signs and symbols for the existence of strong central authority capable of planned action – in antiquity, walls, roads, canals, castles, fortresses, temples and the like, indicated a central authority that is capable of planning. The same holds true for today’s cities: their roads, pavements, highways, public institutions, civil centers, industrial zones and residential areas are often seen as the result of a dominant central authority that plans and controls the city.
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Chapter 13. Complexity, Cognition, and Planning

Abstract
The act of planning accompanies cities from their very origin: The existence of cities, as noted in the previous chapter was interpreted as an indication for the existence of planning. Nowadays, however, planning is a profession and scientific discipline. In this conjunction between planning and cities it is common to make a distinction between planned and unplanned cities that are often called “organic cities”. American cities with their iron grid road structure as well as several of the world’s capital cities are often cited as typical planned cities, and of course, new towns. A ‘new town’ is explicitly defined as a city or a town that was carefully planned from its inception in a previously undeveloped area. On the other hand, “old towns”, old city centers such as European middle ages towns are often described as unplanned “organic” towns and cities (e.g., Hillier and Hanson 1984). But see Chap. 5 on this issue.
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Chapter 14. Learning from Paradoxes about Prediction and Planning in Self-Organizing Cities

Abstract
Since early days paradoxes have been useful (and enjoyable) analytical tools; mainly due to their capability to expose things that are wrong when everything appears to be right. Zeno paradoxes are a good example to their use in antiquity, while in modern science theoretical physics stands as a domain where paradoxes are intensively used. This is not the case with cities and their planning, however. This chapter introduces paradoxes as useful means to study predictions in the context of cities and their planning. It discusses several city planning paradoxes and suggests seeing their origin in the complexity of cities and in the role played by cognitive maps and information exchange in complex, self-organizing cities.
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Chapter 15. CTC, Social Theory Oriented Urban Theory, and Planning

Abstract
In previous chapters we’ve seen that there are several interesting resemblances between complexity theory and social theory and as a consequence between CTC and social theory oriented urban theory. We have further seen, however, that beyond the latter similarities, there is a fundamental difference between CTC and social theory oriented urban studies: The starting point of SMH and PPD urban theories is society at large when the city is perceived as a representation of the larger and more fundamental system – society. CTC as interpreted in this book, start from the nature of the city itself as a complex self-organizing system.
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Chapter 16. A Self-Planned City

Abstract
The process of planning as developed during the 20th century was (and still is) characterized by two basic properties: Firstly, it was developed as a top-down hierarchical process in which the national planning authorities produce large-scale national plans, within which regional planning bodies plan their regional plans, within which urban planning authorities produce their urban plans and so on down the hierarchy to neighborhoods and below. The major socio-spatial-political entity in such a system is the nation-state and indeed planning is seen as its executing arm. In such a system it is just natural that planning ideas and innovation should come top-down by the planners – a situation that might often imply a nondemocratic planning reality – as the story of advocacy planning testifies.
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COMPLEXITY, COGNITION AND URBAN SIMULATION MODELS

Chapter 17. Revisiting Cognitive Dissonance and Memes-Derived Urban Simulation Models

Abstract
In previous chapters we’ve suggested SIRN as a cognitive approach to urban dynamics. In the present chapter (and in the one that follows) the aim is to explore the implications of SIRN to urban simulation models (USM). This is done, firstly, by an examination of four interrelated properties that typify SIRN and distinguish it from most CTC approaches of urban dynamics: (1) it is a comprehensive CTC; (2) it is a cognitive CTC in an innovative way; (3) it suggests perceiving urban agents as a complex systems; (4) it implies a separation between agents’ intention and behavior.
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Chapter 18. CogCity (Cognitive City): A Top-down→Bottom-up USM

Abstract
In Part II above we have introduced several cognitive capabilities of humans and have discussed their implications to various aspects of cities as complex self-organizing systems. The present chapter extends this discussion and examines the implications to USM. This is done by developing CogCity (cognitive city) as an urban simulation model that explicitly incorporates in its structure the role of three cognitive processes that as illustrated in Part II above, typify the behavior of human agents: information compression, cognitive mapping and categorization. The discussion below starts by introducing the three cognitive capabilities and their general implications to USM (Sect. 18.2). Next a specific urban simulation model is introduced (Sect. 18.3) and some of results of its simulation runs are presented and discussed. The specific urban scenario the model simulates describes entrepreneurs as urban agents who come to the city in order to find a location and build on it a certain building they “have in mind”. By so doing they in fact construct the city as a 3D landscape. Finally, Sect. 18.4 summarizes the two main innovative features of CogCity: Firstly, that it is a cognitive USM that makes explicit use of some of the cognitive capabilities of humans. Secondly and as a consequence of taking cognition seriously, CogCity is a top-down bottom-up urban simulation model in the sense that agents take decisions in a top-down order and then act in a bottom-up sequence.
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Chapter 19. Pattern Recognition, SIRN and Decision Making

Abstract
In this chapter we elaborate on Haken’s demonstration that the synergetic paradigm of pattern recognition can be used as a conceptual and mathematical framework for the study of decision making in general and in the context of cities in particular. The elaboration includes an extension concerning cognitive mapping, a reference to Tversky and Kahneman’s studies on the psychology of decision making, and a reformulation in terms of the notions of IRN and SIRN as elaborated in Chap. 7. The discussion throughout the chapter follows the above description.
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Chapter 20. Decision Making, Conflicts and Time in a Synergetic City

Abstract
This chapter extends and elaborates on ideas presented in the previous one. In particular we address the question how urban agents, e.g., persons or families, may take decisions about occupying specific locations in the city. This decision has to agree with an attractiveness function between agents and locations. While this appears a standard question of most if not all complexity-driven urban simulation models, the procedure outlined here is innovative by several means. First, in line with our claim in Part II that cities are dual complex systems, and in line with the notion of SIRN, the model presented in this chapter treats every individual agent in the city as a genuine self-organizing system. Capitalizing on the concepts of synergetics, the behavior of each agent is described by an order parameter that emerges as a result of interactions between the agent’s internally represented properties and aims, and the externally represented properties of locations in the city. Second, it explicitly implements the competition between agents as well as the (more abstract) competition between the available flats at the various locations in the city. The model shows how the competition between agents and flats simultaneously affects the attraction between them or, more colloquially speaking, the attractiveness of flats. Third, it explicitly considers changes in time in that the competition between agents over locations, as well as the attractiveness of locations to agents, is time-dependent. In more general terms, presented below is a dynamical model that searches for the optimal distributions of urban agents over locations. The model maximizes the global attractiveness of the ensemble and accounts for various conflicting situations. Its solutions show that, depending on initial conditions, both optimal as well as suboptimal configurations can be reached.
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Backmatter

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