The significance of Induction Cities lies in the search for better 
solutions to given conditions. 
What were the conditions that Web Frame had to solve? 
There were three issues: 
1. Restrictions on space.
2. Conditions imposed by each component. 
3. The extension of the given space. 
The first of these was an absolute condition allowing no margin 
for improvisation, just as one cannot choose the site when designing a building above ground. 
As for 2., any variety of forms and quantities is possible under a 
Computer Graphic simulation, but in reality, conditions are imposed 
by the kind of installation that can be carried out. For example, it is 
difficult to achieve an intersection at the same point of five frame 
tubes with an angular variation of one degree each. Individual 
parameters were established to allow for automated clearance of such specific conditions. 
This is essentially the same kind of task as designing structural 
frames for conventional architectural work. 
The third condition -- spatial extension -- became another 
parameter. By specifying the approximate position and volume of 
component parts, the desired space is generated. This is a flexible 
specification. 
It is a lot of work to develop a program that will satisfy just 
these three conditions. Several attempts were needed to get it right. 
Even an automated program for designing a free frame "closed" 
in three dimensions turns out to be difficult. There are restrictions on the solid angles that can be employed, and all points must be joined together. 
The issues here are different from those of conventional space 
frames assembled in regular fashion from materials with fixed angles. 
Simply because the degree of freedom is great, divergences can occur and lead in unpredictable directions. 
Freedom can, of course, readily slip over into chaos. 
But an important element of this concept is to give the 
appearance of chaos while in fact obeying certain regularities. 
While the result may appear to be arbitrary and willful, the 
necessary conditions are rigorously met. The same can be said of 
chaos and of all forms of complex phenomena. 
The coexistence of freedom and harmony! This sounds like a 
catchphrase put forth at some kind of meeting by people fully aware that such a thing will never come about in reality. But this is not an empty slogan. We are (just) beginning to see signs that it can be realized. 


Introducing Arbitrariness / Returning from "Design-less" to Design 

With the Web Frame project, we have moved forward from the 
first phase of Induction Cities into the field of 'esthetic' evaluation. 
That is our fourth objective. 
In the first phase, we selected as the basis for our criteria of 
evaluation such quantifiable variables as exposure to sunlight, 
distance, gradients, wind speed and resistance, etc. In the case of the City of Generative Neighborhoods project, we defined "interesting" by means of certain formulae and thus introduced a factor of sensibility, but we were not evaluating whether the resulting plans were after all interesting or not. 
With the Web Frame project, however, we tried to go beyond 
the principle of randomness (to which we have thus far adhered) and bring into play some measure of arbitrariness. 
By arbitrary, I do not mean that we are inputting directly 
specifications for factors such as space or forms. What we intend 
rather is a program to satisfy "fuzzy" criteria such as "enjoyable" or "dynamic." 
The designer's hands, tied up until now, will begin to move, just 
a little. But the hands in question are not human -- they are artificial. 
At this point, however, we ran into a surprising (though not 
entirely unforeseeable) difficulty. 
The method used for the programs for the City of Generative 
Neighborhoods allowed for the definition of "enjoyable" on the basis of specific attributes, but the results did not meet our expectations. 
One reason for this was the complex three-dimensional spaces 
and forms in which the Web Frame had to unfold. Another factor was apparently the rigid spatial limitations of the available site. 
It seems that methods based on complexity theory cannot 
become really effective without ample space for implementation. The practical results of natural selection, for example, can only begin to appear in wide savannas or large oceans where numerous species of life have room to live and compete. 
Also, by contrast with evaluation criteria based on clearly 
definable indices, viable indices for the matters of sensibility or 
feeling are difficult to pin down. 
And of course implementable designs are more difficult to 
achieve than research results. We are not playing a game like SimCity. 
After any number of initial efforts, the program did not seem 
able to deliver the kinds of good solutions we were hoping for. We 
were stuck. 


Living Creatures / Self-evolving Programs 

At this point, we have to return to our earlier question, what is a 
"good" thing? In City of the Sun Goddess, we chose as an index for evaluation exposure to sunlight, and in On Demand City, our index was distance. 
Except for the requirement of meeting these conditions, 
everything was randomized. We made a point of not manipulating the output of the programs. 
The program for City of the Sun Goddess generated an 
aggregate that looked like a natural colony. In the case of On Demand City, the resulting plan for location of facilities was similar to that of a naturally occurring town. In both cases, that is, some aspect of "naturalness" showed up. Naturalness is something that everyone can understand. 
By excluding the intentions of a designer and letting criteria of 
the form of physical laws determine the outcome, a plan with all the "persuasiveness" of a natural phenomenon was generated. 
Would it be unfair to call that persuasiveness "beauty"? 
Let me put it this way: It is the physical laws underlying their 
regularity that cause us to feel that snowflakes or the waves on the surface of a river are beautiful. 
The basic principles outlined above (1, 2 and 3) are at work in 
the Web Frame project, as well. But the results vary widely depending on how the parameters are established. There is a large margin for instability. In short, it is close to chaos. "Naturalness" does not emerge. 
If a large number of parameters are combined and finely tuned 
in the pursuit of naturalness, an enormous amount of trial and error is required. In practice, such an approach is not feasible. We end up 
making the best of what comes out and giving up. At this rate, there is no much difference from designing the whole plan by hand. 
One means of avoiding this kind of impasse is to incorporate 
laws of "nature" in the program. 
Why not introduce some principle from nature -- for example, 
the laws of motion governing the movement of waves -- that gives 
such a sense of pleasure? 
If dynamic force can create for us rational and beautiful patterns, 
then it should be enough to add to our program a simulation of 
dynamic force. 
There is a history to this line of thinking. When Gaudi 
suspended weights from inverted models to make decisions about 
designing, he was in effect performing an analog computer simulation. 
The same can be said of the use of soap bubbles, in the 1960s, 
as the basis for designing the structure of membranes. 
Today, we don't have to use either weights or soap bubbles. We 
can use Navier-Stokes equations and deploy supercomputers to 
simulate fluid dynamics. But the literal application of natural laws 
looks tediously like mere imitation of nature. Induction Cities is not 
seeking to reproduce natural phenomena. 
It would be more to the point to incorporate principles which 
don't bear directly on the requirements. 
We began searching for effective code that would be both more 
specific and simpler. 
At the same time, we began examining the possibilities for 
another approach. 
This other approach was to have the program search for its own 
evaluative criteria. 
The program is run and then its output evaluated by human 
beings. 
The results are scored -- are they satisfactory, or not quite good 
enough? 
When this process is repeated often enough, the program, 
instead of simply outputting more plans, begins to generate plans 
which are likely to receive higher scores. If you praise the program, it learns… "AIBO" was a first step in this direction. 
If the process continues long enough, the solutions output by 
the program should improve markedly -- in theory at least. 
The idea is to create a program which is based on this 
mechanism. 
What is interesting about this is that the question of what is 
"good" is never given a clear answer. 
(It is true, of course, that if the results obtained by this process 
were analyzed, it would be possible to get a clear picture of the values involved. What you are seeking to do is just this… A table of 
evaluative criteria is drawn up. For the Induction Cities project, the 
mechanisms for devising a program are in principle also the means for analysis.) 
As if by magic, good plans are generated, even while the 
criteria for evaluation are not clarified. This is our trump card for 
escaping the impasse of making value judgements. 
Learning functions for software in simple form are built into 
word processors, today. 
If we pursue this idea further, to the point that the program 
learns to modify itself, there should be no objection to calling this an "evolutionary function." What we do call it should depend on how advanced (smart) the program really is. 
For these purposes, inheritance algorithms are also useful. This 
program is still undergoing development. 

Structure-generating Program / Wing 

The Architectural Seed germinates deep in the ground, 35 
meters below the city. (Seeking more water, more light…) After a 
time, its underground stem reaches the surface and there, a flower 
blooms. 
This is called "Wing." 
Wing is a ventilation tower. It houses the ventilation and air-
conditioning equipment for the entire subway station: a respirator for the space below the ground. 
Wing is the respiratory organ put forth above ground by an 
invisible, subterranean stem. 
For its structure, we sought a mechanism of auto-generation 
using a computer program. The program is not yet completed, 
however. What we show here is a model of what the structure will 
perhaps look like once the program is operative. 
We attempted here to incorporate the structural dynamics -- 
something which was not a condition to be solved by the program for Web Frame -- and made this a primary condition. 
To design a conventional structural frame, a simple grid-work 
is devised, weight is applied, and the effects are calculated. Proper 
materials are selected to meet the load requirements of those portions under greatest stress. The same materials are then used throughout the frame. This is true for both rigid frames and tubes, and regardless of whether the shape is a box or is curved. 
But if materials are selected not by this uniform rule but varied 
from section to section as actually necessary, a different form of frame will appear. 
And if we substitute the word "design" for "necessary," still 
other forms will emerge. This is what I have attempted to do with 
Wing. 
The framework is thick and large which forces are greatest, and 
thin where forces are weak. 
Materials are fused at the joints to better withstand transmitted 
stress. 
Instead of joining pillars to beams, the material extends, 
separates, rejoins and forms a single overall frame without distinctions between verticals and horizontals. 
Moreover, the arrangement of structure and material is 
optimized so nothing is superfluous. 
Its structure is that which has already been achieved by living 
plants. 
Wing is a model of one form that frames will take when such 
structures can be generated automatically. 

Civil Engineering and Architecture -- Collaboration 

The kind of processes described above could not have been 
achieved without cooperation between civil engineers and architects. 
In Japan, the world of those responsible for building structures 
such as subways and bridges is quite separate from the world of 
architects. Until now, it has been rare for the two to join forces and 
work on a single project. 
The size of the concourse and passageways of subway stations 
is normally determined to meet the minimum requirements prescribed by applicable statutes. Decisions about station interiors are usually made in the same way as those concerning the size requirements for mechanical facilities, engine rooms, etc. In that sense, it seems to me that considerations of spatial values and issues of comfort have been neglected. 
The idea, then, was to take into the world of civil engineering 
the concept -- so fundamental in the world of architecture -- of 
designing not only for technical needs in response to the given space. 
At the same time, this project provided architecture with something 
that transcends the designing of individual buildings: a perspective on the infrastructures of a vast city. It seems unnatural, after all, that these two points of view should be sharply demarcated. 
This should not remain a one-way street -- this project was a 
first step towards achieving mutually shared perspectives through 
collaboration. 

Keeping Track of Where We Are / Space Navigator 

The stations of Tokyo's subways are intricate labyrinths. This 
station is linked to three other subways by underground passages, and is connected to a surface railway station as well. 
The overlapping, multi-level tubes of the subway station make 
up a space as complex as that of a topological model. Once inside, it is easy to lose all sense of direction. 
Indeed, the difficulties characterizing this space are already 
apparent from on the ground of the city of Tokyo. 
Let's try walking along the streets of this city. Roads which 
appear to follow a regular grid turn out to curve little by little. 
Adjacent to lot number one we find lot number five, followed by lot 
number two, and so on. The numbering system forces one to give up any desire to seek principles of order. Knowing an address in Tokyo is no guarantee that one will be able to find the way to one's destination. 
Without the kind of iconic information afforded by a map, the 
destination cannot be located. This is why car navigation systems and services for relaying maps to cellular phones are bound to become prevalent. 
In the world under the ground, all of these difficulties are 
magnified. 
In the life sciences, evolutionary change which tends to 
reinforce a given characteristic is called orthogenetic evolution. The neck of the giraffe gradually becomes elongated; the reindeer's antlers assume larger and more complex forms. 
In regard to the structures of space, the underground world of 
Tokyo's subways may indeed be a more 'evolved' version of the space above ground. If that is so, then perhaps the complex topologies of the subways can be appreciated as a positive aspect of this world. 
If this indeed an evolutionary advance in some sense, then one 
measure has been taken to reinforce this tendency. 
Web Frame was inserted into the subterranean world as a 
modeling of its elaborate spatial structures. And yet, whatever 
pleasures may be had in wandering through these spaces under the 
ground, the utility of the subways as a means of transportation 
depends on readily understandable access. Ordinarily, this is 
facilitated by the use of signs. One has to be within reading distance of a sign to follow its directions, though. Where are we now? Should we go right or left from here? It would be simpler if we didn't need to rely on signs for orientation. What is needed is a means of enhancing the 'imagability' of space. 
To meet this need, we adopted two measures. 
One was to enhance the distinctive character of unitary spaces. 
The second entails indicating differences in direction. 
Distinctively different materials were used for the two 
concourses, the two sides of the platform walls, and for columns at 
either end of the platform, and so on. 
If it were possible to tell right from left, beginning from end, 
front from back, without paying too much attention, but rather by a 
sense of feeling, then even walking though a labyrinth might be 
enjoyable. 
Memorable visual clues -- the gilt edge of the platform, the 
concourse with the translucent ceiling, and so on -- can provide 
helpful spatial orientations. 

Visual-tactile Sense / Seeing and Touching 

When we look at ice, its coolness is conveyed right to our hands. 
Looking at a wooden wall, a sense of warmth seems to reach our skin. 
When we look at things we feel their textures at the same time. 
To see is to touch. When we look at something we graze its 
surface with our eyes, stroke it with our vision. 
The senses of sight and of touch are intimately connected. 
Works of art that demonstrate this connection are installed in 
the subway concourse. 
One part of a wall is lined with Braille type and enlargements 
of Braille blocks, brief fragments of words. 
Letters remain legible whether they are large or small. Braille 
type is different. There is an absolute limit to the practical size of 
Braille. Enlarged beyond that limit, it becomes illegible. These are 
words, but have the shape of words which cannot be read. These 
shapes convey the meaning of size. 
Braille type is read with the fingertips. If one touches metal 
Braille type to read the words "texture of wood," two distinct 
sensations are superimposed. What happens when we read the word "metal" inscribed on a wooden block? 
The sense of touch, words within the mind -- the tactile sense of 
visible materials, words in the mind. 
Where the senses of sight, touch and meaning are concerned, 
there arises an indefinable shifting from consciousness to feeling and back. 
This artwork attempts to instigate that small wavering in 
between mind and sensation. 
Along with such works, we have left hints of the same design 
throughout the concourse. In the vortices of the handrails on the 
staircases, in the thick steel plates of the public telephones, in the 
mirrors of the restrooms, made of glass that appears freshly wiped free of raindrops, in the swelling of pipes in the platform columns, and elsewhere. 
If one touches any of these things on an impulse, a quiet sense 
of that wavering between visual and tactile sensations is bound to 
make itself felt.

Developing New Materials

As always we undertook to develop new kinds of materials for
this project.
Because the project site, a subway station, is a heavy-duty
facility, we could not count on attentive maintenance, so the
conditions required of materials were demanding.
One solution was to maximize available light without relying
solely on installed lighting fixtures. Phosphorescent acrylic was
applied to the inner surfaces of the glass; its edge-lighting effect
encourages the passage of light from within. This was employed in
some of the platform columns and in the lines of the finishing walls
inside the passageways.
The glass used in Wing is coated with titanium dioxide for
enhanced self-cleansing, to minimize maintenance. We had intended
to use similar self-cleansing treated materials elsewhere in the projectbut the technology is not yet stable enough for practical use. We hopethat such technology will become available in the near future.