15 fundamental properties

Recurring identifiable structural characteristics of objects and buildings which manifest in their geometric features.

Objects and buildings which have life all have certain identifiable structural characteristics. The same geometric features keep showing up in them, again and again.

Alive systems exhibit the 15 properties, dead systems don’t

The fifteen properties are present in systems that are alive, and absent from systems that are dead.

Systems in space which have these fifteen properties to a strong degree will be alive, and the more these properties are present, the more the systems which contain them will tend to be alive. […]

The things and systems in the world which are most dead — the most image-laden buildings and artifacts, the most sterile housing projects, the most damaged ecological systems, the most poisoned streams — will have these properties to the least degree.

“Dead” objects and artifacts often have these characteristics:

• image-laden, egocentric
• sterile
• damaged/damaging (in the sense of ecology)
  • e.g., a poisoned stream and its consequences

15 ways centers strengthen each other

The 15 properties are the principal ways in which centers strengthen each other.

I believe that these properties arise because they are the principal ways in which centers can be strengthened by other centers. They are, if you like, fifteen ways of talking about centers, and the way that the existence and life of centers dominates the existence of life in the world.

Each property describes one type of spatial relationship between centers that causes them to intensify each other. Through such intensification of centers, space becomes coherent or unified and thus more alive.

Each of the properties describes one of the possible ways in which centers can intensify each other. Each one defines one type of spatial relationship between two or more centers, and then shows how the mutual intensification works in the framework of this relationship.

In effect, the fifteen properties are the glue, through which space is able to be unified. The fifteen properties provide the ways that centers can intensify each other. Through the intensity of centers, space becomes coherent. As it becomes coherent, it becomes alive. The fifteen properties are the “ways” it comes to life.

The 15 properties

1. Levels of scale
2. Strong centers
3. Boundaries
4. Alternating repetition
5. Positive space
6. Good shape
7. Local symmetries
8. Deep interlock and ambiguity
9. Contrast
10. Gradients
11. Roughness
12. Echoes
13. The void
14. Simplicity and inner calm
15. Not-separateness

Why 15 fundamental properties?

The 15 properties are not independent and can overlap.

Learning to recognize and apply the 15 properties is difficult.

Contemporary architecture avoids the 15 properties.

Family resemblance of systems which have life in them

The 15 properties roughly define a subset of all possible systems: the family of systems which have life in them.

Roughly (and I must emphasize that this is only true to a first approximation), the fifteen properties define the enormous family of systems, among all possible systems, which have life in them.

The properties make it possible to establish connections between systems that look different at first, but share these properties as part of their complex morphology.

The fact that it is possible to characterize this family at all is surprising. The family which is so defined is very complex morphologically. Superficially, the many examples in this chapter look dissimilar. Each belongs to its own time and place. They vary in culture, climate, and technology. But more deeply, there is a sense in which these different cases all look the same. They all have the same deep quality; one sees the same structure, again and again, throughout the examples.

Thus we have a grip, perhaps for the first time, on the actual physical and geometrical character which living systems have. It is not too much to say that any building which has life in it, must be a recognizable member of this family.

How Alexander discovered the fifteen properties

Alexander discovered the fifteen properties through observation, when he empirically took notes about different objects and buildings, by comparing them and determining which has more life and eventually recognized geometric patterns in those things that had more life and missing these features in those things that had less life.

#book/The Nature of Order/1 The Phenomenon of Life/5 Fifteen fundamental properties#