[The fullest available description of the fifteen fundamental properties of living structure can be found in the four volumes of The Nature of Order — particularly Book One, The Phenomenon of Life (NOPL) . The argument is that living structure, wherever it appears, is composed of fundamental structural features — roughly fifteen of them, at least. Living structure, according to the argument, is in fact unlikely to be discovered lacking too many of these fifteen properties. They are consistently present. The discovery of these properties is the result of decades of attentive observation by architect, builder, and author Christopher Alexander.

The aim of these observations — to better understand the nature of things around us, the order of life, in order to participate in its construction — is not one that should be discarded. Instead, we can cultivate it. One way available to anyone is to simply notice with clear-eyed joy those things that give one life, no matter how small they are, and to welcome the idea that the life they give is real.]

The boundary around the earth performs invaluable functions -- and it is beautiful.

Boundaries of a shore: tidal zone, beach, grassy bluff.

Shores, porches, steps, arcades, sidewalks, patios, alcoves. All are examples of places between places, or forming the edges of larger spaces.  They are places people often enjoy occupying for long, lazy stretches of time.   Although many of these structures function primarily as zones of transition, our fondest associations of them are as places not where we move but where we casually meet, where we sit and stay and feel comfortable letting the world pass us by. We feel extraordinarily comfortable in those substantial and lively boundary places that sit between one place and the next — when they become vibrant living centers in and of themselves.

Golden Gardens, Seattle, WA. The beach is an obvious boundary (between ocean and land), but so is the thick rise of green trees a boundary (between beach and city) which intensifies the life of the beach and helps make it what it is.

Almost anywhere a shift from one level of scale to another occurs in living structures, you will find a boundary functioning as a transition between the levels.

The purpose of the boundary which surrounds a center is two-fold.  First, it focuses attention on the center and thus helps to produce the center.  It does this by forming the field of force which creates and intensifies the center which is bounded.  Second, it unites the center which is being bounded with the world beyond the boundary.  For this to happen, the boundary must at the same time be distinct from the center which is being bounded, must keep this center distinct and separate from the world around it, and yet also have the capacity of uniting that center with the world beyond the boundary.  Then the boundary both unites and separates.  In both ways, the center that is bounded becomes more intense. (NOPL, 158-9)

The particular functions of various boundaries, however, are diverse and often bear no analogous relationship at all to boundary functions in other structures.  Nonetheless, boundaries abound.  The structural similarities at all levels of scale are evident.  For example, Alexander compares the enormous corona of the sun to the thick wall of a cell, which controls the communication between the nucleus and its immediate environment.

Consider the surface of the sun: there is a zone there, many thousands of miles deep, where the flames of the sun’s inner fire shoot out into space.  This is where the near vacuum of space interacts with the inner nuclear reactions of the sun’s interior, an interaction so peculiar, in its own right, that it occupies a massive volume.

Or, at a very different scale indeed, consider the wall of an organic cell, a massively thick structure where all the flow in and out of the cell is controlled.  The cell wall is as thick, almost, as the interior of the cell itself. (NOPL, 254-5)

The delicious orange boundary around the seeds of a cantaloupe. Mmmm.

These Boundaries, as with Levels of Scale, do not take just any size: they are often incredibly large, sometimes as large as the thing being bounded.  This is true for the nucleus of the cell, the atmosphere of the earth, the bark of a tree, the lips of a mouth.  As with Levels of Scale, size matters:

If the boundary is very much smaller than the thing being bounded, it can’t do much to hold in or form the center.  A two-inch border cannot hold a three foot field. […] For instance, the lips as the boundary of the mouth are similar in size to the mouth; an arcade as the boundary of a building is on the same order of size as the building; a truly generous window frame with deep reveals as the boundary of a window is of the size of the window itself; the marsh as boundary of a lake; the capital and base as boundary of the column.  In all these cases the boundary is very large compared with that which is being bounded.  (NOPL, 159)

The marsh as boundary of the lake. University of Washington bird sanctuary, Seattle.

A concrete "window" of mine. A concrete "window" of mine.In a real way, it is nothing but boundaries. The concrete frames the open spaces even as the open spaces reveal the shape of the concrete. The positive and negative spaces bound one another, and the back and forth-ness of this is because the boundaries are as large as what they bound. And of course windows themselves are boundaries. (I believe, in fact, that windows are more beautiful, and make us feel more alive, when they are broken up like this. Large uninterrupted panes of glass seem desirable, but I do not think any of us truly like them as much as we might think we do.)

Here are cardboard mock-ups of steel braces that will form substantial boundaries between the rafters and the massive alcove entrance beam in the chapel project.

(Even in structures with little life, the degree of life can be seen to consist in the presence of the same properties which create the intense life in others.  Below are two work places with little life — but one has more than the other:

This grouping of offices enjoys the (small) degree of life it has thanks to the arcade in front of the doors. Also, the shade provided by the retaining wall and trees is a structure enhancing feature -- and a boundary.

If you doubt the degree of life in the last shot, compare it with the (lack of) life here. The "arcade" is essentially two-dimensional, and there is no functioning boundary whatsoever between the building and the parking lot.)

Boundaries work to distinguish and unite the larger centers which they separate, and they need substance of their own in order to do this.  However, in addition to their size, it is important to notice that boundaries, when they are living centers, are themselves made of other living centers (Strong Centers).  So, for instance, the boundary that is the shore includes within it (at least) the tidal zone, the beach, the grassy bluff; the cantaloupe has a rind, the fruit, and the pocket of space around the seeds; the arcades have their columns, and the bases and capitals of the columns, and the spaces between the columns; the boundary between the buildings of Lincoln and the highway includes the gravel area and the porches, and the step up to the porch.  As Alexander puts it,

If we apply the rule repeatedly, it says that every part, at every level, has a boundary which is a thing in its own right.  This includes the boundaries themselves.  They too have boudnaries, each of which is a thing in its own right.  What seems like one rule, then, is a pervasive structural feature of enormous depth, which is in effect applied dozens or hundreds of times, at different scales throughout the thing. (NOPL, 16)

Almost every bit of ground in this photo functions as a boundary. The life of the buildings is immensely enhanced by the deep porches, and the gravel drive in front of them provides a nice thick boundary between these porches and the cars that speed by. The shoulder (or "berm," as my writerly wife is wont to call it) of the highway is a boundary, as well as the large rock and timber fence, and the lawn as well. Just imagining the absence of any of these boundaries reveals the degree of life they lend to the living structure of this place, Lincoln. Even the highway lends a degree of life, uniting (even as it separates) the two sides of Lincoln in a way that can be appreciated.

Boundaries are a beautiful structural feature, and they are pervasive in most living structure.  As I suggested in the opening paragraph, I believe they are places which slow us down, relax us, make us feel safe, like we have time.  This is not what makes them a fundamental property, but rather what suggests that our deep liking is truly entwined with the nature of living structure — even when we’re unaware of it, just chatting leisurely on the steps.

Many patterns in A Pattern Language exemplify the functions and need for boundaries in our built environment, from Neighborhood Boundary (86) to Closets Between Rooms (913).  Additionally, these include: Subculture Boundary (75), Frames as Stiffened Edges (1059), Alcoves (828), Window Place (833), Thick Walls (908), Gallery Surround (777), Arcades (580), Outdoor Room (764), and Necklace of Community Projects (242).  There are many more, and I would encourage you to peruse the list of patterns, found here.

Living Neighborhoods.org, one of Alexander’s own sites, also offers a description of Boundaries, with many fine pictures.

~*~***~*~

This week’s photo of light, speaking of boundaries and places of transition, is a poor quality shot of a place with unexpected and subtle life to it: the gates at Portland Airport.  There is something about this room which, as far as airport terminal gates go, is able to make me feel just a little more myself, a little more relaxed, than others I have been in.  I think it is mainly due to the fact that it is on ground floor with the tarmac.  Something about this is very calming (again, given the fact these places are generally associated with anxiety), and I feel it, however slightly, whenever I am there.  In this shot the light is bouncing off the wet tarmac and into the room.