2017/10/25 09:30 Michael Mehaffy, “Horizons of Pattern Languages: Software, Cities, Planet”, PLoP

Plenary @michaelwmehaffy Pattern Languages of Program PLoP2017

This digest was created in real-time during the meeting,based on the speaker’s presentation(s) and comments from the audience. The content should not be viewed as an official transcript of the meeting, but only as an interpretation by a single individual. Lapses, grammatical errors, and typing mistakes may not have been corrected. Questions about content should be directed to the originator. The digest has been made available for purposes of scholarship, posted by David Ing.

Intro by Takashi Iba

Michael Mehaffy has collaborated with Christopher Alexander from the beginning of the 1980s

  • Generative codes
  • Future pattern language
  • Urban planning

Independent consultant, appointment with Oregon State University

  • Books on urban architecture and design

Participated in the 20th PLoP conference

[Michael Mehaffy]

PLoP 2017 -- Michael Mehaffy

30,000 foot talk

Not a software person, some familiarity:

  • Programming on Cray
  • Then minicomputers with 10K
  • Early Apples in the 1970s

Got interested in electronic music

  • Architecture as frozen music
  • Led to working with Christopher Alexander

Got to scales of cities, towns, settlements

  • Now the main focus:  we’re doing badly on planning cities

Most recently been involved with Habitat III:  Sustainable urbanization

  • Some Alexanderian ideas in the document, due to community involvement

Other UN intiatiatives

  • COP21 Climate Negotation
  • Sustainable Development Goals

Institution involved with:  The Future of Places, in Stockholm

  • Focus on public space:  the spine of the city, where everything comes together
  • Access to the benefit of the public city
  • Main focus of the new urban agenda
  • The Centre for the Future of Places, KTH

Rapidly urbanizing around the globe

  • Not all bad
  • Urbanization is often fragmented

Two varieties

  • Slums
  • Market rate development — resource inefficient, greenhouse gas emissions

Have to do a better job in both cases

  • Cities can interconnect us with each other and resource
  • Connected catalytic system
  • Develop cultures and innovations, economy

Mike Batty and Peter Ferguson:

Problem:  there’s an operating system for growth that produces predictable result

  • People can protest before it’s built
  • It’s often bad
  • Degradation of a quality of life

Have to take on reforming growth

Economically unsustainable

  • Map of Houston Texas, where the global financial crisis happened, in the houses that that people had loans they couldn’t afford
  • Denver:  foreclosures, drive until you can afford
  • Challenge in managing technology
  • Ward:  A technologist, but more a person who thinks about how people work together

Techne + Logos:  the logical of making things work together

Conundrum:  The Internet

  • 20 years ago, we were excited to share information
  • What happened:  clickbait, insipid discussions, that drown out the real quality in the Internet
  • Twitter trolls
  • Also wider culture, race to the bottom, Wrestlemania with nuclear weapons
  • A serious issue: How we’re improving or not improving a constructure problem-solving approach

Edward Sapir 1920s, Culture:  Genuine and Spurious [see http://www.katarxis3.com/Sapir.htm]

  • Technological, yet cultural

Want to meet common challenges:  climate change, inequality, sustainability

Breaking down knowledge

  • NASA web site
  • Claims and counterclaims
  • Some people interested in economic impacts, benefactors
  • Creates distortion in ability to agree

Contrast to Wikipedia:

  • Page on Battle of Hastings
  • Not in dispute
  • Google search will often show Wikipedia citation as the first
  • Wikipedia used to be the butt of responses
  • Wikipedia is getting smarter, as the rest of the Internet is getting dumber
  • Wikipedia page:  Global warming conspiracy theory


  • We need to gather up knowledge that isn’t reliable
  • Want it sufficient for shared action
  • Science and languages do this

Wiki as Pattern Language, paper workshop at PLoP 2012 [see http://www.hillside.net/plop/2013/papers/Group6/plop13_preprint_51.pdf ]

  • Ward thought of wiki not only as way to distribute patterns, but it’s a pattern language itself
  • Pattern of overlap:  Herbert Simon, The Architecture of Complexity, 1962, near-decomposability with overlap
  • Alexander, Notes on the Synthesis of Form, in semi-lattice
  • Have useful information

Notes on the synthesis of form:  mereology, parts and wholes

Mereology:  part-whole relations

A City is Not a Tree, 1965

  • Rock-paper-scissors problem

Republished article in 2016 book, with commentary

Structure of a pattern

  • Forces of a door, hinges and knob
  • Can’t just put them any other way, have to get strong forces right
  • Look at strong forces and weak forces, and can slide them around
  • If there’s some relationship, e.g. to entrance, you have a whole new pattern, e.g. room
  • Nearly-decomposable hierarchy

In architectural patterns, it’s a physical decomposition

  • It’s an evidence-based process, some things that work, some that don’t

Don Norman, The Design of Everyday Things

  • Affordances

Alexandrian form, 7 parts:  images, upward hyperlink, downward hyperlink

Another conundrum:  Why have pattern languages not been more influential in the world of the built environment?

  • Google hits:  260,000 in architecture dwarfed by the number in software

Newman and Bhat:  Multi-cellular life from a pattern language approach [see “Dynamical patterning modules: a “pattern language” for development and evolution of multicellular form” at http://doi.org/10.1387/ijdb.072481sn

  • Malfunctions of life, like cancer

Why are architects only a small portion of all pattern languages?

  • Architects are weird?
  • Defective in the built environment?
  • Something going on in technology and culture:  collaborative and management models, open source systems

Things pointed out by Jane Jacobs in 1961

  • Put finger on momentous changes

Looking at another book with Jane Jacobs compared with Christopher Alexander

  • Web as compared to hierarchy

Cities Alive, new book by Michael Mehaffy

Network science:  new discoveries

  • Certain connections are important
  • Cellular automata generating
  • Morphogenesis
  • Fractals as scale-free patterns

Seeing patterns in evolutionary history

A new urban agenda

In Portland, Sustasis Foundation

  • Met Ward during recovery of New Orleans
  • New patterns

Potential of federated wikis

  • Same idea as wiki, but it’s federated, meaning that there isn’t just one structure, can copy and clone and work in different versions, and then bring back together
  • Can adapt more locally
  • Open source peer-to-peer development
  • Allows more evolution
  • Handles quantiative data
  • Transparency of data, click through

There are some issues with fed wiki, need some innovations to make it more useful

Could take architectural patterns to the next level

Ph.D. dissertation, building scenarios on greenhouse gas

  • Can model the predictive outcomes, based on the patterns interconnecting with each other

Could use fed wiki for financial, etc.

Key remaining issues with the Pattern Language book

  • Not enough ability to customize, 253 patterns got frozen, not flexible to change, write, throw out
  • Hard to interface with web, when trapped in book form
  • Not enough information for architects, about structure

The Nature of Order was about that

  • How to operationalize the pattern language, when it comes to geometry
  • How does nature do this?
  • Nature doesn’t make a blueprint of the final state
  • It’s more like a code or recipe for growing form


  • We can draw from biological systems
  • Learn from traditional forms, in structures not much different


  • Can look at regions in space
  • Architectural plan, urban plan, any structure — can identify patterns
  • Sets  or systems with distinctness
  • Living systems amplify generative relationships
  • Processes of exchanging signals and nutrients

Example of face:  Penelope Cruz, can find centers that result in people thinking she’s beautiful

  • If you remove the relationships, get a strange doll-like characteristic
  • Loses its life
  • Order, underneath it, is not a living system

Structure-preserving transformations

  • Can map geometries
  • Harold Egerton’s photo of drop into a thin film of milk:  new structure happens spontaneously
  • Alexander thinks life is a strong emergent possiblity
  • Can talk about layers, scale, strong centers
  • With 15 categories, Alexander can account of almost all structural properties

Was 12, became 15

  • The last few that were added:  e.g. simplicity and inner calm
  • The properties were in the order that he thought about them

Aesthetic phenomena is our portal into the deeper universe

  • Also transformations, in boundaries
  • Can see in natural structures, and traditional architectural structures

Now in a period where we have been using simple industrial processes

  • Geometric forms have become stripped of interconnected characteristics
  • Snap-on technology
  • Standardization

This is what Jane Jacobs was talking about

Death and Life of Great American Cities

  • Still back at World’s Fair 1958

Sprawl model from CIAM Model 1938

  • Victor Gruen‘s Shopping Mall
  • Supercampuses
  • Dendritic pattern, rather than web networks
  • Problem with hierarchical structure, not being walkable

Not just physical structure, it’s process

  • Like cooking a pizza, have to have web of interconnections in great cities, that allow creating benefits
  • Have to have biological process, using stepwise processes
  • This is the essence of generative codes

As opposed to a brittle, template based approach, using segegated zoning, etc.

Relationship between bottom-up and top-down

  • More like gardening than carpentry

Thinking about all of these as strategic toolkits, to put things together

Issue is the same for software, as other domains

  • How to speed up the feedback cycles?
  • How to get better adaptive quality?  Especially for externalities, e.g. resource depletion
  • Can identify just the key elements

Ward Cunningham:  how do you generate rather than specify?


A lot of success in the software world, architecture has less success.  In architecture, will patterns to grow to match success

  • Do believe that.
  • Have to deal with it
  • 253 patterns have a copyright problem, now people just getting over it
  • Federated wiki:  need some barriers removed
  • In software, didn’t have the static evolutionary problem, writing in code

Curation.  Paradox between our study and inspiration from nature, and the fact that we’re part of nature.  If we’re only one system, what does curation mean?

  • We have a nested series of systems, all with the same fundamental structures
  • Then have new ways of dealing with problems
  • Used to think language …

Why use the word problem?

  • What happens naturally
  • We’re not creating new superstructures of abstraction, can do more things, e.g. create cities
  • Termites can lay down simple
  • On the other hand, human beings generate a lot of noise
  • Curation:  idea that separate the process of creating content, from the process of editing it
  • In science, have the bucket and the searchlight

Curation.  We are intentional.  There are differences in intentionality.  Half of salmon make it back.  Over time, things die.  Alexander patterns are about generating life.  What do you do about death that occurs.  Patterns of repair?

  • Accounting for death?  Have to account for death
  • It’s not a harmonious process, it is a process that creates waste
  • Jane Jacobs:  Cities have lots of issues, conflicts, because human have issues and conflicts, and people bring them.  Hope to not evolve into an age of disaster.  Hope to evolve to more complexity
  • Intentionality:  an articulation of some deeper evolutionary tendency, towards complexity
  • We want more life, more complexity
  • More deeply embedded, in the structure of things
  • More articulated teleology:  an ideal state … that gets us into trouble, but that how we plan and we plan badly sometimes

If not planning, need to do some curation?

  • Self-organization versus planning
  • It’s not versus:  planning for self-organization

Complexity theory.  Form.  Definition of the pattern as a problem-solution form is adapted to the problems evoked here?  Ways to account for the evolution of things?  Could we try to adapt a stronger definition of patterns, to insert into the natural flow of things?

  • Patterns are language-like ways of expressing our intentionality of the way we want our ways configured
  • Anti-pattern as something that the world should not look like
  • Embodied in the structure is some intentionality of not getting scalded
  • If evolves, still need the human hand to guide it
  • Design methods movement, which was started to guide good design, Alexander disowned 10 years after dissertation, need a human being to guide the process
  • It only works if you have your own life
  • Patterns express intentionality, our way of life
  • Map of the reality

Take-away:  Not emphasizing the nature of pattern language.  Build more on it.

  • In planning, moving away from a static model
  • Won’t know what it will have in the end
  • However, should have the forces right, in the most important ways
  • Human-centered

#pattern-language, #plop, #plop-2017