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. Tim Berners-Lee, Seeing With Fresh Eyes A City Is Not a Tree hierarchywww
Cool URIs don't change An Essay by Tim Berners-Lee www.w3.org What makes a cool URI? A cool URI is one which does not change. What sorts of URI change? URIs don't change: people change them. The User Interface of URLs www
Deliberate acts I do not know what one should call the landscape of a long cultivated countryside, or the enchanting pattern of lights which shows at night time in a modern city seen from overhead. Are these not works of art? It is scarcely justifiable to say that these things have taken shape by chance. Each part of them has been made as it is by what seemed a deliberate act, and it need not necessarily be assumed to be a matter of chance that the results of many acts of many men over a considerably period of time should harmonize together aesthetically. David Pye, The Nature and Aesthetics of Design The Timeless Way of BuildingA Pattern Language evolutionurbanism