hierarchy
Excursus: Homage to the Square^3
The problem with trees
Many systems are organized hierarchically. The CERNDOC documentation system is an example, as is the Unix file system, and the VMS/HELP system. A tree has the practical advantage of giving every node a unique name. However, it does not allow the system to model the real world. For example, in a hierarchical HELP system such as VMS/HELP, one often gets to a lead on a tree such as:
HELP COMPILER SOURCE_FORMAT PRAGMAS DEFAULTS
only to find a reference to another leaf: Please see
HELP COMPILER COMMAND OPTIONS DEFAULTS PRAGMAS
and it is necessary to leave the system and re-enter it. What was needed was a link from one node to another, because in this case the information was not naturally organized into a tree.
The brilliance of notion
This, I think, is the brilliance of Notion, and what makes it one of the best examples of “fidelity to digital information” that I’ve come across. The structure of the app reflects the structure of the web itself: digital content is purposefully formatted, like semantic HTML elements, and exists in a hierarchical structure (directories on the web, nested pages in Notion), yet can be linked and referenced to create a complex network of information. And pages in Notion reveal the structure of the information: when nesting a page within a page, the child page always displays on the parent page. There’s no way to create a child page that doesn’t display on a parent page, no way to obscure the structure of the information. The semantic structure of Notion reflects the semantic structure of the web itself.
Separation and connection in all things
Truchet's approach was more topological than geometric, and the qualitative aspects of pattern take priority over the metric ones. His principles provide a kind of metaphor for the hierarchy of separation and connection in all things.
Walk Appeal
Walk Appeal promises to be a major new tool for understanding and building walkable places, and it explains several things that were heretofore either contradictory or mysterious. It begins with the assertion that the quarter-mile radius (or 5-minute walk,) which has been held up for a century as the distance Americans will walk before driving, is actually a myth.
Both images below are at the same scale, and the yellow dashed line is a quarter-mile radius. On the left is a power center. As we all know, if you're at Best Buy and need to pick something up at Old Navy, there's no way you're walking from one store to another. Instead, you get in your car and drive as close as possible to the Old Navy front door. You'll even wait for a parking space to open up instead of driving to an open space just a few spaces away… not because you're lazy, but because it's such a terrible walking experience.
The image on the right is Rome. The circles are centered on the Piazza del Popolo (North is to the left) and the Green radius goes through the Vittorio Emanuele on the right. People regularly walk that far and then keep on walking without ever thinking of driving.