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Architecture's New Scientific Foundations, Part 2

Architects often assume that complexity, in general, must be designed. That's a misconception, and rarely conducive to human wellbeing.

By Nikos A. Salingaros
May 12, 2015

Editor’s note: ArchNewsNow is presenting this series of lectures by the mathematician, urbanist, and architectural theorist Nikos A. Salingaros. Nikos has worked for many years with legendary architect and software pioneer Christopher Alexander in helping to develop a new scientific basis for architectural design. Despite the crucial importance of this work for implementing a truly sustainable design practice, it remains outside the architectural mainstream. So, we are very happy to be able to present parts of a new book-in-progress by Nikos, as an exclusive and original project. He is appearing on ArchNewsNow for the first time. © Nikos A. Salingaros, 2015, published here with permission from the author. Read Part 1 here.



Chapter 4A. Adaptive vs. Random Complexity, Part 1


Adaptive complexity cannot be designed


Nature and the built environment are both complex. But they don’t always have the same type of complexity. Nature shares much of its organized complexity with (portions of) what we build, and this affects our body and eventually our health. The greatest healing effects are found in man-made environments of traditional and vernacular character (Mehaffy & Salingaros, 2015). Architects would love to know how to use mathematical knowledge to design complex forms, and then build them as actual structures. But “natural” complexity is not “designed” in the sense that one person – the designer – determines all details beforehand.


Architects and the educated public often assume that complexity, in general, must be designed. That’s a misconception, and rarely conducive to human wellbeing. Designed (invented) complexity cannot automatically reproduce or imitate the organized complexity found in nature, except in the most superficial, non-functional manner. And yet we certainly want to understand how to employ complexity so as to generate a better, more adaptive environment. True sustainability depends upon creating genuinely organized complexity, where all different structural scales link together coherently. The “organized” part is its most vital characteristic, hence the most difficult to achieve.


That doesn’t stop architects from trying to “design” complexity. Computer programs generate complex, innovative shapes that look impressive on a screen. But these designs are relevant only to style, not to functionality. They fail to embrace the primary quality of evolutionary adaptation, the organized response to variable conditions. Many complex contemporary structures are mathematically disorganized, hence random. There exists a simple criterion for determining whether a structure’s impact on adaptation is organized or random: if any other structure could be erected in its place, and its degree of adaptation to conditions does not rise or fall, it is randomly adaptive.


Look at any one of a number of recent award-winning buildings meant to be museums of contemporary art, public libraries, concert halls, or government offices. Their shapes are interchangeable (except for specialized interior features that actually serve a function). After such a virtual switch, the substitute building does not adapt any better to its site, nor to its surroundings. The original did not adapt, and neither does any contemporary alternative. The reason is that we have a group of fashionable buildings that do not care to adapt to anything at all.


Random design, typically conceived by architects as jagged surfaces, or as curved anomalies in a building’s interior or exterior form, is not meant to be adaptable to human needs. It is abstract art, design as styling, a pursuit dealing with appearance and not the function of a building or the needs of its users. Using random input for generating a design might produce a visually striking sculpture. If that’s what the client wants, then everybody concerned is satisfied – except perhaps the hapless user in those cases, hardly infrequent, where client and user are different people.


The methods of generating organized complexity are to be found rather in techniques of design that are deliberately adaptive. Those techniques organize existing elements that are responding to actual and latent complexity, which makes it imperative to be sensitive to and gather feedback from such responses. Forget about generating complexity: the sequence of steps followed in adaptive design will generate it for you. All you have to do to design adaptively is to organize emerging complexity as it is being generated in each step. By focusing on adaptation and organization, the result will be organized complexity that is adaptive to human use and physiology.


How to build up organized complexity


The secret to adaptive design is to organize the emergent complexity during the design process, instead of trying to eliminate it. The standard techniques for organizing complexity (Alexander, 2001-2005; Salingaros, 2006) include:


(i) Connecting the parts of a system or structure through various geometrical means, most often with multiple connections.


(ii) Aligning multiple adjoining flows so they reinforce each other (but not to a rigid axis or grid).


(iii) Creating local symmetries (but not an imposed global symmetry).


(iv) Implementing spatial correlations using similarities at a distance and scaling symmetries (i.e. similarity under magnification).


(v) Repeating things adaptively, so that they will vary in each repetition. Monotonous repetition, on the other hand, implies a lack of adaptation.


(vi) Building up a system or structure using a sequence of adaptive steps, where the organized complexity arises from an evolutionary process.


(vii) Recognizing complexity as the result of dynamic processes rather than as the result of a conventional static appliqué of “art.”


These tools create organization. A sequence of adaptive design steps generates the complexity required for a specific project brief or set of functions. The designer implements a step-by-step procedure that allows feedback into the design process, at the same time as it is being carried out. Design components arise from adapting every detail to human dimensions and movements, and to the human psychological response to spaces and uses. This procedure requires paying attention to all scales.


Applied to the development of a street or other multiple or single structures, to the construction of a single building, or components such as a staircase or a porch, the method requires feedback. Begin by defining those forms and dimensions that are constrained by the project. Those are less flexible (or not at all) after construction. Experience the shape or space using your own body and, with the help of other volunteers, make possible adjustments. Use full-scale mock-ups from cheap materials that help to feel the actual dimensions. Then decide on the next most-rigid part of the design, model that somehow, and again use feedback for adjustments. Proceed downwards in this manner to the smaller and smaller scales, and don’t hesitate to change what’s on an initial drawing.


In adaptive design there exists no regularization – as with monotonous repetition, for example – because that reduces the information content of a complex system. Adaptation breaks monotony. The principle of variation in music illustrates a crucial point: each variation on a theme is not generated by arbitrary randomness. Instead, it comes from following an organizational framework that generates a particular variation from the basic theme. Randomness is out of place in tonal music. The direction of a variation is not entirely unexpected but intuitively anticipated by the listener. It is a carefully premeditated and controlled excursion by the composer into tonal possibilities, applying the constraint of organization and coherence. A similar phenomenon animates the development of adaptive design.


As human beings, we find ourselves in a complex world that we did not create, but which we manipulate and transform in profound ways. We see complexity embodied in different forms all around us, and in response we constantly produce “structures” having various degrees of complexity. Those structures involve the systems we create, more or less unconsciously, to negotiate the complexities that we encounter. Buildings and streets that help us do so are often outgrowths of their designers’ understanding (conscious or not) of how successful buildings and streets actually work. People tend to forget that there is a dynamic reason for observed complexity. A working mechanism and its variety of supporting frameworks generate a complex product that depends on dynamics and organization.


The complexity of traditional buildings is highly organized, motivated by forces analogous to those that drive natural and biological complexity. The traditional built environment was shaped adaptively to contain our movements and vital actions. A building itself doesn’t change in response to our needs (except when renovated), but we experience buildings over time as expressions of ever-evolving techniques for designing them. Those techniques incorporate the knowledge acquired from the success or failure of their predecessors at addressing our needs.


We embrace here neither a deliberate attempt at randomness, nor its opposite, the attempt to create simplicity for its own sake. Instead, a determined yet unconscious drive mimics in human creations the high degree of organized complexity found in nature. Nature provides the template for useful complexity, and human beings are hard-wired to follow it. In doing this, we are not really copying nature’s forms, but instinctively try to reproduce one of its essential mathematical qualities.


When we do observe either randomness (as disorganization) or extreme simplicity (as uniformity) in traditional buildings and urban fabric, it is there because it is the simplest and easiest energy alternative; or it is a byproduct of forces that have built up organized complexity elsewhere. In this second case, randomness or simplicity are left over after focusing on organizing complexity nearby, where function is more important. In nature as in traditional settlements, there are functional reasons for what is happening and where it occurs, and it does not arise merely from a designer’s whim.


Conserving versus reducing complexity in computer science


Computer scientists conjecture that functional complexity is conserved. When a specific task is simplified, what actually happens is that the organized complexity needed to perform it is merely shifted somewhere else. For example, simplifying a computer-human interface throws the complexity onto the invisible part of the system (Tesler, 1984). Within software, simplifying on one abstraction level usually shifts the complexity to another level. You cannot just throw out complexity from a functioning system without damaging it.


Another type of implementation transfers complexity from hardware to software. Building a more elegant computer (inside, among its circuits, not its surface appearance) requires paying the price of increased complexity elsewhere. Attempts at modularization, driven by the desire to simplify the interchangeability of hardware modules, shift the complexity burden from hardware onto software and interface: again, there is no net reduction in organized complexity (Coward & Salingaros, 2004). Today, our cleanest interfaces are driven by millions of lines of software code: a huge increase in software complexity leading to an equally huge improvement of “user-friendliness” compared with their more clunky ancestors.


Implications for the built environment


Conservation of functional complexity in the built environment provides a key insight into socio-geometric processes. A given set of human actions and movement, together with the structures that adaptively contain them, define a working threshold of organized complexity. They are linked into one system. Often, on a grand scale, stylistically driven simplification reduces the organized complexity of the built environment, with serious negative effects. To accomplish the same task or goal, human actors often must handle far more complexity than before. If people are unable or unwilling to assume the burden of additional complexity, a useful activity may cease. Thus, a net reduction of complexity in the built environment can eliminate useful life functions.


But here, complexity is actually lost. The analogy with computer complexity no longer holds true, since computers are designed to execute specific functions. The objective of simplification is easier use, not less capability. Users of information and communication technology demand more features making computers and electronic devices easier to use, but they would cry out if functionality were reduced. They wish to do what they always did and more, and in an easier, faster, and more efficient manner, calculated in electricity usage, or keystrokes, etc.


In contrast with the user-driven example of computers, our built environment is replete with instances where geometrical simplification has killed off formerly lively and vibrant community life. A good example here is replacing human-scale intricate urban fabric with giant, faceless monoblocks. This invariably arises from misguided, top-down urban policy implementation. The lesson is that complexity in the built environment (assuming it is the kind that contains and supports living processes) is inseparable from human life. In many places, simplistic design replaced the variety in components of healthy individual and social life with a deadening sterility that has damaged cities and even entire regions.


Adaptation requires a high level of the right type of organized complexity, which is not something that can be “designed” in the sense of the term that architects understand. Design that imposes either simplistic or random forms for reasons of style, aesthetics, or political ideology avoids the need to adapt to the complexity inherent in human life and society. Such image-driven design is not useful to and is often detrimental to life. Indeed, governments consciously use architectural and urban simplification as a tool of social engineering. Minimalist forms, spaces, and environments have unexpected problems of functionality that their designers, concerned only with their style, never imagine.




Christopher Alexander (2001-2005) The Nature of Order, Books 1-4, Center for Environmental Structure, Berkeley, California. Book 1: The Phenomenon of Life, 2001; Book 2: The Process of Creating Life, 2002; Book 3: A Vision of a Living World, 2005; Book 4: The Luminous Ground, 2004.


L. Andrew Coward & Nikos A. Salingaros (2004) “The Information Architecture of Cities”, Journal of Information Science, Volume 30 No. 2, pages 107-118. Reprinted as Chapter 7 of Nikos A. Salingaros (2005) Principles of Urban Structure, Techne Press, Amsterdam, Holland; reprinted 2014, Sustasis Press, Portland, Oregon and Vajra Books, Kathmandu, Nepal.


Michael W. Mehaffy & Nikos A. Salingaros (2015) Design for a Living Planet: Settlement, Science, and the Human Future, Sustasis Press, Portland, Oregon and Vajra Books, Kathmandu, Nepal.


Nikos A. Salingaros (2006) A Theory of Architecture, Umbau-Verlag, Solingen, Germany; reprinted 2014, Sustasis Press, Portland, Oregon and Vajra Books, Kathmandu, Nepal.


Larry Tesler (1984) “The Laws of Interaction Design”, in Dan Saffer (2009) Designing for Interaction, 2nd Edition, New Riders/Pearson, London.



See also:

Part 1: Architecture's New Scientific Foundations
A new book-in-progress aims to change the way architecture is evaluated and, thus, to change the way it is practiced.


Nikos A. Salingaros collaborated with visionary architect and software pioneer Christopher Alexander, helping to edit the four-volume “The Nature of Order” during its 25-year gestation. He has been recognized by the Alfred P. Sloan Foundation, the INTBAU College of Traditional Practitioners, and was one of the “50 Visionaries who are Changing Your World” selected by UTNE Reader in 2008. In Planetizen’s 2009 survey, he was ranked 11th among “The Top Urban Thinkers of All Time.” Author of seven monographs on architectural and urban design translated into several languages, his work links human-scale urbanism to developing architectural movements such as Biophilic Design, Evidence-Based Design, P2P Urbanism, the Network City, Generative Codes, and Sustainable Architecture. Dr. Salingaros holds a Ph.D. in Theoretical Physics, and is Professor of Mathematics at the University of Texas at San Antonio. He is also on the architecture faculties of several universities, and directs Ph.D. students in architecture and urbanism around the world.


(click on pictures to enlarge)

Photo of Bharatanatyam dancer by Marie-Julie Bontemps, 2014.