Principia Cybernetica Web

About the Principia Cybernetica Server

Principia Cybernetica Web is one of the oldest (registered July 1993), best organized, and largest, fully connected hypertexts on the Net. It contains over 2000 "nodes" (web pages), numerous papers, and even complete books. Some 28,000 files (about half of which are text documents) are downloaded every day from this server, that is, over 5 million a year. Over ten thousand links point to documents in this web.

Although Principia Cybernetica Web has received very positive reviews, the work is of course never finished. The material in this web is continuously being added to and improved. Nodes followed by the mention "[empty]" don't contain any text yet, only a menu of linked nodes. Some important results have not yet been converted to hypertext, some of which may be found in the papers in our FTP-archive.

Comments about content and presentation of the information are appreciated. If you have any technical problems, questions or suggestions on our Web, please contact the "Webmaster", Francis Heylighen cybernetica [at] Comments about the content of a node can be addressed to its author(s). You can also directly annotate each node separately, or add general comments to the User Annotations.

Mirror servers for faster downloading

We apologize for difficulties you might have in getting files from the main server at the Free University of Brussels: Internet connections between Belgium and especially Latin America are often overloaded.

To remedy the problem, we have set up a mirror server at Los Alamos National Laboratory in the USA. This server is likely to provide much faster connections for users in the Americas, and possibly other regions. The files on the mirror server are automatically updated every day, to reflect changes in the original server in Brussels. If you are not sure which server is best for you, you can simply try repeatedly to get the same files from either server (by clicking on the "Server: EU" or "US" options in the menu bar), and see which connection responds most quickly.

Although you can bookmark pages on the Los Alamos mirror, we would ask that if you make links to PCP web documents in any of your own public web pages, you would use the address of the original server: This will avoid possible confusion when links to the same page actually refer to different addresses, so that search engines would consider these to be two different websites. (search engines determine the importance of a webpage on the basis of the number of links pointing to it).

Another solution for people with a slow Internet connection is to download the main documents of the website as a single file in compressed zip format (2.1 Mb, but this file is somewhat out-of-date). This is much to be preferred to the use of a robot or automatic program for downloading a whole website page by page, since these robots usually open as many connections to the server as possible, thus making it difficult for other users to receive pages in the meantime.

Copyright© 2002 Principia Cybernetica - Referencing this page

F. Heylighen,

Mar 15, 2002 (modified)
Oct 14, 1999 (created)


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