Structure
33. The basic cell of human settlement is a physical scalar unit that is an expression of its community—politically, socially, culturally, economically, etc. The settlement will only function properly only if this unit is not fragmented in any way.
Law 1 states that the physical fabric of a settlement is an expression of a community’s values—political, social, economic, cultural, etc. The material manifestations of these dimensions are critical to its well-being and are established at a series of different scales (Law 0 and Law 8). However, some are more important to their respective communities than others and unique to each settlement.
Ray Oldenburg echoed this thirty years later in his influential book The Great Good Place. Within, he describes the importance of the “third place”—inclusive social places separate from home and work—and their roles in developing a healthy community. His work cites a number of historical examples, from the French Cafe to the American Main Street, that have served this purpose over time. As one can see, they are different and range in scale, and Oldenburg suggests that they served as critical “informal public gathering places” that unified neighbourhoods, among other important social functions.
Similarly, in Built for Change, Anne Vernez Moudon cites the ‘Building/House’ as the basic cell of the city, while the lot acted as the “basic cell of neighbourhood” (Moudon, 1989, p. 144). She goes on further to discuss how tenure and inhabitation act as ways of controlling the residential cell.
Whatever the scale, Doxiadis states that these important physical places must remain intact in order for communities within a settlement to function properly.
FURTHER READING (full citations found in reference list):
- Constantino Doxiadis – Ekistics: An Introduction to the Science of Human Settlements
- Ray Oldenburg – The Great Good Place and “Our Vanishing ‘Third Places” http://plannersweb.com/wp-content/uploads/1997/01/184.pdf
- Anne Vernez Moudon – Built for Change: Neighbourhood Architecture in San Francisco
34. All communities, and therefore, all settlement scalar units tend to be connected to each other hierarchically. Every community of a higher order serves a certain number of communities of a lower order, and the same is true of specific functions with each unit.
Although the physical scalar units that comprise a settlement are co-dependent (Law 8), the relationship between these elements has not been discussed until now. This law establishes a hierarchical structure connecting units within a larger system. This is in keeping with some of the pioneering work around hierarchy theory at that time, such as Arthur Koestler’s (1967) The Ghost in the Machine and Lancelot Law Whyte, Albert G. Wilson, and Donna Wilson (1969) (Editors) – Hierarchical structures .
Since the release of Ekistics, advances in knowledge around ecological systems, complexity theory and hierarchy theory have been more definitively applied to biological structures, as well as cities. These have served to substantiate Doxiadis’ claims.
With respect to urban structure, nested hierarchies have been a particular focus. Nikos Salingaros, for example, cites Hierarchy as one of the eight interconnected rules or “generic principles” of urban form. He states that Hierarchy links many distinct elements at specific scales interdependently (another one of his rules): that is, the relationship is not symmetrical (Law 35).
Salingaros is in good company, from Spiro Kostof who describes cities as “….locked in an urban system, and urban hierarchy” (Kostof, 1991, p. 38). to N.J. Habraken who opens the discussion up to a variety of hierarchies related to settlement. These include, but are not limited to, hierarchies of circulation networks, enclosure, inclusion, and territory.
Also noteworthy is the work of Serge Salat, who suggests that, in order to create sustainable, resilient cities, three different types of hierarchies must be harmonized: “The hierarchies of built forms (urban blocks, neighbourhoods, districts, cities), the networks of communication, and the urban services connect these units on every scale and such human activities as living, working, commerce, education, and leisure from so many superimposed hierarchies” (Salat, 2011, p. 29).
Since this idea a little abstract, a quick example is worth describing. Consider a situation where a town acts as the main centre of a set of lower order (smaller) settlements, while simultaneously serving a larger (higher order) city. NASA’s View of the World at Night, that clearly depicts clustered constellations of settlements, clearly shows these types of hierarchical relationships. Similarly, one could imagine a small, neighbourhood level shop existing at a “lower level” than a regional distributor from which it gets its products.
FURTHER READING (full citations found in reference list):
- Constantino Doxiadis – Ekistics: An Introduction to the Science of Human Settlements
- Arthur Koestler – The Ghost in the Machine
- Lancelot Law Whyte, Albert G. Wilson, and Donna Wilson (Editors) – Hierarchical structures
- Nikos A. Salingaros – Principles of Urban Structure
- Spiro Kostof – The City Shaped: Urban Patterns and Meaning Throughout History
- N.J. Habraken – Structure of The Ordinary
- Serge Salat – Cities and Forms: On Sustainable Urbanism
- NASA – Views of the World at Night – https://www.nasa.gov/mission_pages/NPP/news/earth-at-night.html
35. The fact that all communities tend to be connected in a hierarchical manner does not mean that this connection is an exclusive one. Many other connections at the same level or at different ones are equally possible, but for organizational purposes the connection is hierarchical.
Law 34 introduced the issue of hierarchy and nested scales that connect scalar ‘units’ of settlements. It also presented the work of N.J. Habraken, Nikos Salingaros, and Serge Salat that speak to this concept. Doxiadis elaborates on this by recognizing that, given the complex nature of the co-dependent systems, settlements have a variety of connections “in all directions.” As such, there are a number of possible relationships between elements, some of which may not be hierarchical. This gets even more intricate when secondary and other forces (Law 11) are considered. Despite the latter, Doxiadis states that generally speaking “any organized activity should follow a pattern of hierarchical connections” (Doxiadis, 1968, p. 307).
Of particular relevance to this law is Salingaros’ discussion around another one of his “generic principles of urban form,” Interdependence. Described immediately after the principle of Hierarchy (Law 34), he suggests that elements on different scales do not depend on one another symmetrically. That is, “a higher scale requires all lower scales, but not vice versa.”
Serge Salat, who builds on the insights of Salingaros, elaborates: “A successful urban web is organized by an ordered fractal hierarchy of connections at different scales. It is connected in multiple ways without being chaotic.” He adds, ”If a hierarchical level is missing, the web is pathological. A hierarchy is often established over the course of history” (Salat, 2011, p. 218). As implied in the latter, time is also a related and important factor (Law 14).
FURTHER READING (full citations found in reference list):
- Constantino Doxiadis – Ekistics: An Introduction to the Science of Human Settlements
- Nikos A. Salingaros – Principles of Urban Structure
- Spiro Kostof – The City Shaped: Urban Patterns and Meaning Throughout History
- N.J. Habraken – Structure of The Ordinary
- Serge Salat – Cities and Forms: On Sustainable Urbanism
36. The existence or creation of communities and functions of a higher order does not necessarily mean the elimination of those of the lower one.
This law highlights a fundamental, but often misunderstood, aspect related to hierarchy. Many often assume that the creation of a ‘higher-level order’ ultimately means the destruction of a lower level order, but this is not always the case. The introduction of larger neighbourhood/regional supermarket, for example, does not necessarily lead to the destruction of all small markets. Although the number of lower order functions may diminish, each order has its own function relative to the scale it is a part of.
Local corner stores, therefore, serve the needs of inhabitants that cannot effectively be handled by stores or supermarkets located too far from their homes. Simply put: people can walk to them, and this prevents their elimination, despite the potentially elevated cost of products relative to larger regional retailers.
The birth of the modern supermarket is an interesting case in point, and Doxiadis highlights the fact that when they first appeared, two erred arguments arose. On one hand, advocates of the corner store and the “small scale” opposed the larger supermarkets, describing them as inhuman. On the other, those in favour of the supermarkets denounced “small” as obsolete in the face of the automobile city, seeking to eliminate them entirely.
As stated by Doxiadis, both perspectives were “equally wrong, since there is a hierarchy of functions and communities, and the hierarchical system must function as a whole if the settlement is to function satisfactorily.”
Even more relevant is the idea of a street hierarchy. The advent of the highway did not see the elimination of all street types below it, although many people tried to do so with unfortunate consequences. As stated by Serge Salat, the latter “involved razing the old fabric and inordinately enlarging the urban grid to bring it in line with the major regional throughways. This was the position taken by Le Corbusier, modernism, and the new towns in Frances. We know today that this approach was a failure” (Salat, 2011, p. 191).
Rare circumstances of large-scale destruction aside, most settlements saw highways simply add another level to the existing types of streets.
As an advocate of the “fractal city,” Nikos Salingaros’ offers a more contemporary take on Doxiadis’ insight: that settlements must have structural components of all sizes, across all scales, in order to remain healthy.
FURTHER READING (full citations found in reference list):
- Constantino Doxiadis – Ekistics: An Introduction to the Science of Human Settlements
- Serge Salat – Cities and Forms: On Sustainable Urbanism
- Michael Southworth & Eran Ben-Joseph – Streets and the Shaping of Towns and Cities
- Nikos A. Salingaros – Principles of Urban Structure
37. The types of services and satisfaction provided by a settlement’s scale, community and function of a higher order to those of a lower order, depend on cost-distance and time-distance.
As discussed in Law 36, different services and functions relate to different scales of a particular settlement. A simple comparison of the local corner store versus the larger neighbourhood/regional supermarket was described, accordingly. However, in this law, Doxiadis elaborates further by stating that cost-distance and time-distance are important factors contributing to the satisfaction of the inhabitants.
The role of both of these factors has been analyzed and developed further since the publication of Ekistics. As described within the Planning and Urban Design Standards, cost-distance—as opposed to Euclidean distances measured in straight or curved paths—measures distance that “involves the least effort in moving across a surface” (American Planning Association, 2007, p. 334). This has been much easier to measure with the development of Geographic Information System (GIS) softwares that readily allow these calculations.
Time-distance measures, on the other hand, look at the time required to cross certain distances. These have become particularly important for the management of constructions (tunnels, bridges, etc.) as well as transit travel (i.e. transport schedules representing bus locations along transit routes).
As eloquently described by Jarrett Walker in Human Transit, it is worth mentioning that, although travel times are important for good transit design—and are often cited for proposed transit lines—the issue of frequency is equally critical.
The uses of both types of measures aside, it is clear that each continues to play an important role in shaping the distribution of activities, uses and spaces within a settlement.
FURTHER READING (full citations found in reference list):
- Constantino Doxiadis – Ekistics: An Introduction to the Science of Human Settlements
- American Planning Association, Frederick R. Steiner, Kent Butler – Planning and Urban Design Standards
- Vukan R. Vuchic – Urban Transit Systems and Technology
- Jarrett Walker – Human Transit: How Clearer Thinking about Public Transit Can Enrich Our Communities and Our Lives
38. The overall physical texture of a human settlement depends on its scale and the smaller components of which it is composed.
This law has been revised and simplified to capture the essence of Doxiadis’ initial statement, which was riddled with ambiguity. To start, in order to better understand the intent of this law, the term “physical texture” must be defined. Interestingly, Doxiadis failed to provide a specific explanation of the term within Ekistics. Instead, he alluded to it by explaining “textural forces” that acted on human settlements. Within his book, “physical texture” referred to the spatial relationships and distribution of physical elements across the terrain.
Although it is not described as such, the idea of physical texture is related to the idea of a settlement’s “grain”—something that has a more targeted definition. Described by Kevin Lynch as one of the four basic aspects of physical form (alongside size, density, and shape), grain is typically divided into fine and coarse. The former refers to settlement fabrics that have smaller blocks, narrower buildings and, hence, sharper (“finer”) divisions. In contrast, the latter refers to environments that have broader, larger-scale differences. Think medieval towns (fine grain) versus typical North American suburbs (coarse grain).
Given that settlements range in size—from villages to large cities—grain can only be measured across specific scales, with larger settlements being composed of neighbourhoods of varying grain, for example. As such, Doxiadis’ “physical texture” of a settlement refers to the mix of fine and coarse grain elements.
With this in mind, Doxiadis suggests that a settlement’s physical texture is dependent on its scale (neighbourhood, town, metropolis, etc.) as well as the smaller component (what he calls Ekistic modulus) from which is it logically composed. This is best described through an example: a house (the scalar unit) is composed of rooms (smaller component). So, large rooms beget large houses. Similarly, Doxiadis puts forth the idea that small cities are composed of city blocks and, if the latter is large, the texture of this city is large.
Interestingly, he also notes that the smaller component is, itself, dynamic in response to the scale of the settlement. So, if a small city grows to a large city, its city block component gets too small to define its texture, requiring a corresponding jump to groups of blocks or “superblocks”.
Clearly, a certain degree of subjective judgment is required to define what constitutes the proper smaller component unit relative to the scale of settlement. This is addressed a little more in Law 39. However, the idea that the texture of settlement is based on the dynamic interaction of scale and smaller component units remains powerful when thinking about the structure of a built environment. It also reminds us of Anne Vernez Moudon’s insights highlighted in Law 33: that the building/house is a basic cell of the city while the lot is basic cell of the neighbourhood.
FURTHER READING (full citations found in reference list):
- Constantino Doxiadis – Ekistics: An Introduction to the Science of Human Settlements
- Kevin Lynch – “The Form of Cities“, From Scientific American 190, no 4., 1954
- Yuri Artibise – Urban Fabric: The Form of Cities – http://yuriartibise.com/urban-fabric/
- Anne Vernez Moudon – Built for Change: Neighbourhood Architecture in San Francisco
39. The texture of a human settlement changes as its dimensions change.
The major contributors as to what defines the texture of a settlement—scale and its smaller component unit—were addressed in Law 38. But as discussed, the choice of the “smaller unit” was left open. This law addresses the latter in a more definitive way as Doxiadis describes how the house, a group of houses or city block may be a good unit for the texture of a small city. For larger cities, however, these units are too small and therefore require reconsideration. He states: “The texture of larger human settlements should change when the population of a settlement grows from say 100,000 to one million, since the settlement is unable to operate efficiently with a texture of small blocks” (Doxiadis, 1968, p. 309).
He continues, describing that in order for settlements to remain healthy, they must reshape themselves accordingly, adjusting to the new conditions. The addition of new major arteries to allow for more efficient flows of people and goods through the settlement is an example of how a settlement might accommodate growth and change. According to Doxiadis, a failure to evolve and transform—via its own inertia (Law 19)—results in an inappropriate texture.
Anthony E.J. Morris’ historical description of ancient Rome in History of Urban Form Before the Industrial Revolution speaks well to this issue, as he highlights the struggles inherent to the functioning of a city that was born from the growth of the small villages that coalesced into a single urban area across lower terrain. Citing challenges including increased flooding, disease and pollution, he points out that Roman planners, architects and engineers were constantly struggling to cope with the city’s natural and historical context. He states: “Add to these natural problems the planning constraints that resulted from preceding generations’ attempts to overcome them…and it is by no means surprising that ancient Rome, like so many large modern urban centres, was incapable of being comprehensively restructured. At best, there could only be piecemeal ‘town-patching’ measures” (Morris, 1979, p. 42).
As a counterpoint to Rome, Georges-Eugène Haussman’s radical reorganization of Paris’ urban fabric in the mid-19th century—widening streets and connecting monuments across the existing fine-grained city—demonstrates the accommodation of a new texture within an existing city, in response to its growth. The addition of a new scale of street and pubic space added to Paris’ hierarchy of streets. As argued by Serge Salat, this augmented “its capacity for adaptation, and its versatility” through grafting a new scale of the city to the older smaller ones “without eliminating them” (Law 34–35) (Salat, 2011, p. 79).
FURTHER READING (full citations found in reference list):
- Constantino Doxiadis – Ekistics: An Introduction to the Science of Human Settlements
- Anthony E.J. Morris – History of Urban Form Before the Industrial Revolution
- Serge Salat – Cities and Forms: On Sustainable Urbanism
- Anne Vernez Moudon – Built for Change: Neighbourhood Architecture in San Francisco