The Origins of Pattern Theory (Part C)

The Origins of Pattern Theory,the Future of the Theory, And The Generation of a Living World

by Christopher Alexander


C. What the future holds in store: The Generativity Problem and the Generation of a Living World

Let us now consider a problem of magnitude. There are some two billion buildings in the world, about 2 x 109 buildings. Differently stated, the total amount of built stuff is something on the order of about 1012, 1013 square feet of construction. The total amount of built stuff in Manhattan, is somewhere on the order of 109 square feet. If you include all the exterior space in the world as well, the part of the outdoors that is somehow having to do with human beings and is part of our immediate world, gardens and streets and agriculture and all of that, then — for the world — we’re somewhere up around 1014 square feet of constructed designed space.

How are we going to deal with all that? How do we create, or generate, living order in 1014 square feet of construction? What process could possibly accomplish this within, say, one generation — the next 25 years. The effort of architects, no matter how hard we try and no matter how much good will we put in, it does not begin to scratch the surface of that task. All the architects in the world, together, working as they do today, cannot design more than say 1010 square feet per year — a tiny, tiny percentage of what is needed — far too small to be effective.

I have, for many years, thought that this could only be solved by a genetic approach — an approach where deep structure, spread through society, creates and generates the right sort of structure, very much as genetic code creates and generates organisms and ecological systems — indirectly, by letting loose life creating process.

That is what I still believe. But, today, I am convinced that the equivalent of the genes that act in organisms will have to be — or at least can be — software packages, acting in society. If these software packages are life creating, and accepted, and widely enough spread throughout the world, there is a chance we might get a grip on this problem: provided that the software is freeing, liberating, allows each person individual control and decision making power to do the right thing, and to create living structure, locally, wherever they are. This task must fall, inevitably, at least in part, on your shoulders.

The people who were kind enough to invite me to give this speech originally assured me that if I just explained the intellectual history (as I have done so far), there will be those among you who may find it interesting, that somehow they might latch on to it or know how to translate it into something that’s more directly relevant to your own concerns. That is after all, just what you have done in the last five years with pattern languages. There clearly is a useful parallelism between our two disciplines. However, after receiving this invitation, and contemplating the questions I could raise, I started dwelling on a conviction that was growing in me. This conviction led me to feel that there was a deeper coincidence in what you are doing in software design and what I am doing in architectural design. I began to feel that there is a deeper connection, which suggests that the two disciplines might merge in a way that would benefit us both – you in your discipline and me in my discipline. In the next few minutes I will try to sketch the nature of this connection.

As an architect, of course like anybody concerned with these things, I have a passion to try and make these things happen. It’s not enough just to say well living structure isn’t being produced. I have to ask myself…the question I do ask myself…the question all the time is, OK, well, what are we going to do about it? Here we’ve got this poor Earth sinking under the weight of all this dross. And, what are we actually going to do? I do a 10 million dollar project here and I do a 10 million dollar project there. But that accomplishes virtually nothing. Life is short. A few of those projects….and what is it? It is an atom in the proverbial bucket. It’s nothing. All of the efforts of the architectural brethren, even if I can persuade them of the truth of these things. It is still a drop in the bucket. That by itself, will not affect more than a thousandth part, perhaps no more than a millionth part, of the structure covering the built part of the Earth.

When I started out twenty-five, thirty, years ago, I really thought that I would be able to influence the world very fast. Especially when I got to the pattern language. I thought, boy, I’ve really done it. This is going to work. No problem. The patterns are self evident and true. They will spread. And, as a result, the world of buildings will get better. Hey presto.

But it hasn’t yet worked out like that. In practical terms, so far, I’ve done almost nothing. The pattern language, how much has it influenced the environment of the world. A few thousand buildings have been influenced. There are a few people that have lived a few things and been influenced. But, meanwhile, we’ve still got this gigantic amount of construction out there which is defining the world that all of us live in that is still going on in exactly the same fashion. I believe that the cultural process of influence is simply too slow to be able to take care of this problem. In other words, the process by which one discusses these kind of things, shares ideas about them, gradually influences the way people are thinking so that gradually larger and larger percentages of bits of the environment might turn into living structure. That is a very slow process, and I don’t think it is fast enough to do the job. And yet, as an architect, I view myself as responsible for that. Not of course, alone, but as a professional, that is my job is to try to understand how we can get hold of that – the entire structure of built environment, all over Earth — and do something about it to make it better.

For several years I have been asking myself how this effort can be expanded, and strengthened. It must be our aim to make the world’s environment a living structure, within one or two generations. How, realistically, can be that be done?

So, today, I am standing before you, thinking to myself…right, I’m now talking to people who are in a way the core of the computer revolution. You probably realize, I know you must realize the extent to which the world is gradually now being shaped more and more and more, indirectly, by the efforts of all of you who are sitting in this room — because it is you who control the function of computers and their programs. It is the programs that control the shape of manufacturing, the shape of the transportation industries, construction management, diagnosis in medicine, printing and publishing. You almost can’t name a facet of the world which is not already, to some very strong degree, under the influence of the programs that are being written to manage and control those entities or those operations. And this is still in its infancy. How long has this been really going on? Not long. About 10 or 15 years, though of course, the preparation for it goes a lot further back than that. But really this is quite new. It is going to look a whole lot different, even more powerful in its degree of influence.

And yet, as a professional body, I don’t think that you are yet fully aware of it. I’m probably speaking out of turn here but, you know, I’ve thumbed through the proceedings of this conference, for instance. Jim was kind enough to show it to me yesterday. I don’t really see discussion about What, collectively, are computer scientists supposed to be doing with all these programs. How are they supposed to help the Earth? And, yet, the capacity to do that is sitting right here in this room. That is an amazing situation. You have so much power.… but that means that you also have an enormous responsibility.

Is there a chance you might take on the responsibility for influencing, shaping, and changing the environment. Interestingly, I think many of you do also have the inclination. When I had the pleasure of beginning to meet some of the various folks who introduced themselves to me over the last year and a half from the software community, I began to be fascinated by the number of them that were closet architects. Greg Bryant who worked on the 486 chip, is really interested in ecology and is an editor of Rain, an ecological magazine. Bill Joy is writing about workstations in the concrete physical sense that is familiar as an architect. John Gage, chief scientific officer of Sun, is interested in neighborhood schools, and in the process by which people can repair their own physical neighborhoods by working together. Jim Coplien is dealing with social structures in human organizations. Mark Sewell from IBM wants to build houses. Dick Gabriel has as his deepest passion, the writing of poetry: another kind of art. I don’t have a long enough list. But my hunch is that an amazing number of you who got into this pattern game in the pursuit of your normal professional endeavors are also very profoundly interested in the real physical world, and its shape and its design, its deep feeling, its impact on human life. That is, the world in which we inhabit. It is therefore conceivable that you, collectively, could change the very drastic situation of a destroyed environment that I described earlier.

Let me just go back to the structure-preserving unfolding process that I described in Part B of this talk. I talked about this structure-preserving unfolding processes.

When I first constructed the pattern language, it was based on certain generative schemes that exist in traditional cultures. These generative schemes are sets of instructions which, carried out sequentially, will allow a person or a group of people to create a coherent artifact, beautifully and simply. The number of steps vary: there may be as few as a half a dozen steps, or as many as 20 or 50. When the generative scheme is carried out, the results are always different, because the generative scheme, always generates structure that starts with the existing context, and creates things which relate directly and specifically to that context. Thus the beautiful organic variety which was commonplace in traditional society, could exist because these generative schemes were used by thousands of different people, and allowed people to create houses, or rooms, or windows, unique to their circumstances.

When I first hit on the idea of creating, and using, pattern languages, I was inspired by these traditional generative schemes, and thought that I was essentially copying them. However, in the huge effort of creating a believable, new, pattern language, in the 1960’s the effort went entirely onto the individual patterns (their formulation ,verification etc.), and the idea that they were to be used sequentially, one after the other, dropped into the background. In fact, both A Pattern Language and The Timeless Way Of Building say that the pattern language is to be used sequentially. In practice, however, this feature dropped out of site, and was not emphasized in use. As a result the beautiful efficacy of traditional languages and their simple and beautiful sequential nature, disappeared from view.

In our most recent work, that has changed. We are now focusing on pattern languages which are truly generative. That means, they are sequences of instructions which allow a person to make a complete, coherent building, by following the steps of the generative scheme. We have done this for houses, for public buildings, for office furniture layout and so forth. It works. And it is powerful.

Compared to the pattern language that you’ve seen in A Pattern Language these generative schemes are much more like what you call code. They are generative processes which are defined by sets of instructions that produce or generate designs. They are, in fact, systems of instructions which allow unfolding to occur in space in just the way that I was talking about a minute ago (Part B), and are therefore more capable of producing living structure. The published pattern language by comparison is static. The new generative languages are dynamic and, like software, interact with context, to allow people to generate an infinite variety of possible results – but, in this case, with a built-in guarantee of well-formed results. The design that is created or generated is guaranteed, ahead of time, to be coherent, useful, and to have living structure.

You know the pattern language (the one for architecture) consists of these objects which are interesting and which you somehow try to put together. But it’s possible to have processes or procedures which will go much further, actually generate living structure. Because of the complexity of the situation in the world, and because of the way software is going, software that is designed to do this could very rapidly take the world by storm.

Why would computer scientists and software engineers suddenly become responsible for the form and structure of the built environment? Is that not the province of architects, planners, agricultural experts, forestry people, and civil engineers? It ought to be. But the members of these professions are not taking responsibility for the generative approach to living structure – and so cannot produce it. And, as far as I can see, they do not see it coming, and are not preparing themselves to take it on, mentally or professionally. Therefore it will fall to someone else to do it instead.

In history, this kind of unexpected switch is a common thing. When a paradigm change occurs, in a discipline, it is not always the members of the old profession, who take it to the next stage. In the history of the development in technical change, very often the people responsible for certain specialty are then followed by a technical innovation. And then the people who become responsible for the field after the technical innovation are a completely different group of people. When the automobile came along, the people who built the buggies for the horse and buggy did not then turn into Henry Ford. Henry Ford knew nothing about horse buggies. The people who were building automobiles came from left field, and then took over — and the horse and buggy died off.

It is conceivable to imagine a future in which this problem of generating the living structure in the world is something that you – computer scientists – might explicitly recognize as part of your responsibility. Such a change, representing a kind of a level of marriage between you and me, is of an entirely different sort from the one that I was invited by Jim Coplien to contemplate. I was brought here to answer the question “Okay Chris, what new things have you been doing that might spin off and be useful to us in our neck of the woods? Parts A and B of this talk were about that. But this Part C is about something quite different. I want you to help me. I want you to realize that that problem of generating living structure is not being handled well by architectural planners or developers or construction people now, and the Earth is suffering because of it. I believe there may be no way that they are ever going to actually be able to do it, because the methods they use are not capable of it. For you it is different. The idea of generative process is natural to you. It forms the core of the computer science field. The methods that you have at your fingertips and deal with everyday in the normal course of software design are perfectly designed to do this. So, if only you have the interest, you do have the capacity and you do have the means.

I heard a rumor at breakfast that some of the people in this room have begun to worry about their jobs. I have no idea if that is true. But I was told there is an undercurrent of unease as to where all this — software design — is going. There is a huge expanding phenomenon of programming as an art, and yet an uneasiness about where it is all headed? What is it going to do?

My comment on this? Please forgive me, I’m going to be very direct and blunt for a horrible second. It could be thought that the technical way in which you currently look at programming is almost as if you were willing to be “guns for hire.” In other words, you are the technicians. You know how to make the programs work. “Tell us what to do daddy, and we’ll do it.” That is the worm in the apple.

What I am proposing here is something a little bit different from that. It is a view of programming as the natural genetic infrastructure of a living world which you/we are capable of creating, managing, making available, and which could then have the result that a living structure in our towns, houses, work places, cities, becomes an attainable thing. That would be remarkable. It would turn the world around, and make living structure the norm once again, throughout society, and make the world worth living in again.

This is an extraordinary vision of the future, in which computers play a fundamental role in making the world — and above all the built structure of the world — alive, humane, ecologically profound, and with a deep living structure. I realize that you may be surprised by my conclusion. This is not what I am, technically, supposed to have been talking about to you. Or you may say, Well, great idea, but we’re not interested. I hope that is not your reaction. I hope that all of you, as members of a great profession of the future, will decide to help me, and to help yourselves, by taking part in this enormous world-wide effort. I do think you are capable of it. And I do not think any other professional body has quite the ability, or the natural opportunity for influence, to do this job as it must be done.


I’ve enjoyed talking to you very much. Thank you for listening to me and I would be most keen to listen to your ideas on these topics.