It’s a moment of disorientation I’ve had a couple of times — you find a great piece of writing, and think “Wow, this is really going to change things!”, only to discover that it is in fact decades old. The clash of historical vertigo with Internet Now is both wonderful and daunting.
I had that moment yesterday with Christopher Alexander’s A City Is Not A Tree from 1965. Alexander argues that the hallmark of designed cities (Mesa City, Brasilia) is that their builders invariably gravitate to tree-structures, where all sub-units of a similar type roll-up into a single super-unit, und so weiter, which creates an artificial and ultimately damaging simplification. He contrasts this with the structure of organic cites (London, NYC), which are organized as semi-lattices, where overlap and shared function is the order of the day.
Whenever we have a tree structure, it means that within this structure no piece of any unit is ever connected to other units, except through the medium of that unit as a whole.
The enormity of this restriction is difficult to grasp. It is a little as though the members of a family were not free to make friends outside the family, except when the family as a whole made a friendship.
In simplicity of structure the tree is comparable to the compulsive desire for neatness and order that insists the candlesticks on a mantelpiece be perfectly straight and perfectly symmetrical about the centre. The semilattice, by comparison, is the structure of a complex fabric; it is the structure of living things, of great paintings and symphonies.
It must be emphasized, lest the orderly mind shrink in horror from anything that is not clearly articulated and categorized in tree form, that the idea of overlap, ambiguity, multiplicity of aspect and the semilattice are not less orderly than the rigid tree, but more so. They represent a thicker, tougher, more subtle and more complex view of structure.
Like the 1970 Jo Freeman essay on group structure
I pointed to as my inaugural post, A City Is Not A Tree
is resonant in part because Alexander is describing the world we live in without having seen it.
I have an intuition that this essay says something important about planned vs grown communities in general, even when they meet outside the boundaries of real space and even when the architecture in question is an architecture of machines, but I won’t try to pin that down here —- the material needs at least a re-reading before trying to work with the ideas.
Go. Hit print.