IDEA No 8
XANADU
In 1974, Theodor Nelson released a two-part book Computer Lib/Dream Machines. In it, he predicted the home-computer revolution and the World Wide Web.
Dream Machines explores the creative potential of networked computers and introduced the world to hypertext. Nelson calls his vision Xanadu, a multimedia docuverse of interconnected flying pages.
Computer Lib is a call to arms. With the rallying cry ‘Down with Cybercrud’ it demands that ordinary people rise up and claim computers for themselves. The second half of the book, Dream Machines, describes the unlimited potential of branching media and networked content. Nelson called his vision Xanadu.
In Nelson’s Xanadu, text is liberated from paper. A journey through this ‘docuverse’ is controlled by a virtual throttle. As the reader accelerates through the text, gaps appear between words and sentences, which are instantly populated by new words and phrases, which Nelson calls ‘transclusions’. Pulled from other documents, these transclusions add an ever-increasing amount of detail and background information. Push back on the throttle and detail is omitted, while the writing becomes more concise.
Nelson describes Xanadu as a different kind of computer world, based on a different kind of electronic document; he talks of flying pages, deep interconnection and parallel intercomparison. However, his central insight is that content remains separate from structure. Instead of packaging everything into a single file, the page pulls the content point from its source.
Xanadu has never been fully realized but it has inspired every hypertext system since – notably Apple’s pioneering hypermedia software, HyperCard, and Tim Berners-Lee’s World Wide Web. Nelson is unimpressed by both. The graphical metaphor of HyperCard falls into what he calls a ‘virtual reality trap’. Instead of challenging the print metaphor, HyperCard simulates it. He is equally damning of the Web, dismissing it as a gross over-simplification of Xanadu. In his words, ‘HTML is precisely what we were trying to prevent, ever-breaking links, links going outward only, quotes you can’t follow to their origins, no version management, no rights management.’
Nelson is supposedly responsible for more entries in the Oxford English Dictionary than Lewis Carroll. More tellingly, he conceived many of the ideas we now take for granted. Yet Nelson’s key achievement is greater still: he changed our understanding of what a computer was for and who could use it.■
Computer Lib/Dream Machines was the first book about the personal computer, telling ordinary people ‘You can and must understand computers NOW’.