2003-12-03
The Image of the City- typology of image elements
p47
"""
The contents of city images so far studied, which are referable to physical
forms, can conveniently be classified into five type of elements: paths, edges,
districts, nodes, and landmarks. Indeed, these elements may be of more general
application, since they seem to reappear in many types of environmental images,
as may be seen by reference to Appendix A. These elements may be defined as
follows:
1. Paths. Paths are the channels along which the observer customarily,
occasionally, or potentially moves. They may be streets, walkways, transit
lines, canals, railroads. For many people, these are the predominant elements in
their image. People observer the city while moving through it, and along these
paths the other environmental images are arranged and related.
2. Edges. Edges are the linear elements not used or considered as paths
by the observer. They are the boundaries between two phases, linear breaks in
continuity: shores, railroad cuts, edges of development, walls. They are lateral
references rather than coordinate axes. Such edges may be barries, more or less
penetrable, which close one region off from another; or they may be seams, lines
along which two regions are related and joined together. These edge elements,
although probably not as dominant as paths, are for many people important
organizing features, particularly in the role of holding together generalized
areas, as in the outline of a city by water or wall.
3. Districts. Districts are the medium-to-large sections of the city,
conceived of as having two-dimensional extent, which the observer mentally
enters "inside of," and which are recognizable as having some common,
identifying character. Alwats identifiable from the inside, they are also used
for exterior reference if visible from the outside. Most people structure their
city to some extent in this way, with individual differences as to whether paths
or districts are the dominant elements. It seems to depend not only upon the
individual but also upon the given city.
4. Nodes. Nodes are points, the strategic spots in a city into which an
observer can enter, and which are the intensive foci to and from which he is
traveling. They may be primarily junctions, places of a break in transportation,
a crossing or convergence of paths, moments of shift from one structure to
another. Or the nodes may be simply concentrations, which gain their importance
from being the condensation of some use or physical character, as a
street-corner hangout or an enclosed square. Some of these concentration nodes
are the focus and epitome of a district, over which their influence radiates and
of which they stand out as a symbol. They may be called cores. Many nodes, of
course, partake of the nature of both junctions and concentrations. The concept
of node is related to the concept of path, since junctions are typically the
convergence of paths, events on the journey. It is similarly related to the
concept of district, since cores are typically the intensive foci of districts,
their polarizing center. In any event, some nodal points are to be found in
almost every image, and in certain cases they may be the dominant feature.
5. Landmarks. Landmarks are another type of point-reference, but in this
case the observer does not enter within them, they are external. They are
usually a rather simply defined physical object: building, sign, store, or
mountain. Their use involves the singling out of one element from a host of
possibilities. Some landmarks are distant ones, typically seen from many angles
and distances, over the tops of smaller elements, and used as radial references.
They may be within the city or at such a distance that for all practical
purposes they symbolize a constant direction. Such are isolated towers, golden
domes, great hills. Even a mobile point, like the sun, whose motion is
sufficiently slow and regular, may be employed. Other landmarks are primarily
local, being visibile only in restricted localities and from certain approaches.
They are the innumerable signs, store fronts, trees, doorknobs, and other urban
detail, which fill in the image of most observers. They are frequently used
clues of identity and even of structure, and seem to be increasingly relied upon
as a journey becomes more and more familiar.
"""
These five would be useful in any context of dividing up space. What's maybe
interesting is that I seem to remember the brain uses landmarks itself -- I read
an article that said when somebody describes a route to something, the bits of
their brain that are stimulated when *at* certain landmarks light up as they
*describe* those landmarks. The route is a set of symbols, in other words,
abstracted from the experience itself.
What if what Lynch is describing a is a kind of understood folk wayfinding (cf
Dennett's folk psychology), that these elements really do map
almost-or-approximately to hardwired symbol types in the brain? If that's the
case then understand how they relate and the properties of each would be really
important.
In cyberspace, it's nothing but nodes and paths. But there's no concept of
locality, of accidental distance, so there's edges round everything: you can't
see from node to node unless somebody's already made a path.
Districts have to be deliberate too (although I guess it can occur accidently,
or in an emergent sense too: the similar design of blogspot sites; the
sprinkling of "Powered by Blogger" slogans across the www). That's a case of
infoscent: at each node, the subtle trace of every other node.
But landmarks are pretty much impossible.
(It would make a good short story, I think: Consider three nodes joined by
paths, drawn on the page. Actually this network defines a space, not the space
when it's drawn, but the paths and the node *is all there is* (like the
expansion of space-time doesn't expand *into* anything, it creates space as it
goes). But lets be a little silly and pretend that the triangle, the brane
created as a surface described by these arcs is really a space is some other
dimension. What would it look like to view the www from this new viewpoint?
Could it be simulated on the www itself? How about at higher dimensions? Of
course, as soon as you make a page to be this surface, it's no longer a surface:
it's another node. So you couldn't do it with browsers, or with any system that
has a discrete location.)
Mapping to other terminology I've used:
I've also talked about rooms and corridors before. Rooms are nodes with no
intrinsic distance; if you speak in a room it's available to all other points in
that room. These are nodes. Corridors don't really exist online because they
have intrinsic distance: you can exist at different points in the corridor, and
transformations attenuate along the length. These are trails (in Memex) or
dimensions (in ZigZag); they're absent from the WorldWideWeb version of
hypertext.
I've also, when talking about distance, talked about negative distance
(statement-wormholes, cybernetic feedback loops) -- these correspond to paths:
paths are a bit too conduit metaphor, a bit "the channel is independent from the
information", and I'd prefer to think of condensations of conducting space
instead (space over which it's easier to move, where time is less dense), but
it'll do. I've also talked about positive distance, which is distance which
doesn't have to declare its endpoints: it affects nodes around it by virtue of
existing inside another space. Positive distance is created by walls, where
nodes on either side get further apart. It's not really possible to do this
online without controlling the endpoints and breaking the wormholes (links) --
the closest simulation is just deleting a page (and therefore creating broken
links all over the place): walls are magical; they're action-at-a-distance.
Positive distance is edges. With a lot of edges you can create a maze; a maze is
the opposite of a black hole.