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            <P><font size="7"><b>The Open Society<br>
              and its Media</b></font>
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      <p align="center"><b><font size="4">by Mark S. Miller, E. Dean Tribble, 
        Ravi Pandya, and Marc Stiegler<br>
        Xanadu Operating Company</font></b> 
      <p align="center">Originally published in <b>Prospects in Nanotechnology</b>, 
        <br>
        ed, Markus Krummenacker, James Lewis; Wiley, 1995.<br>
        Proceedings of the 1992 <i>First General Conference on Nanotechnology: 
        <br>
        Development, Applications, and Opportunities</i>.
      <p align="center">Somewhat edited OCR, much work needs to be done before 
        this is readable.<br>
        Figures still missing.</p>
      <p>Electronic media present tremendous opportunities for improving the nature 
        of society. I will first talk about how discourse affects society, and 
        how changes in media may improve societal discourse. Then I will describe 
        the Xanadu[<a href="#f1">l</a>] system, and how it was built to achieve 
        these goals. </p>
      <h3>16.1 Improving society</h3>
      <p>Improving society is a difficult task. More generally, improving complex 
        systems is a difficult task. If you cannot figure out which way is up, 
        see if you can figure out which way is down. Doug Engelbart, back in the 
        early 1960s, wanted to explain to people why interactive systems would 
        make a significant difference to their lives, and to their ability to 
        express ideas. In Figure 16.1, the origin on the axis is what people were 
        doing at the time--writing with pencil and paper. When he found himself 
        unable to communicate to people how much better things could be, he contrasted 
        their current experiences with how much <i>worse </i>things could be. 
        He tied a pencil to a brick, handed it to people and said, &quot;Okay, 
        now write.&quot; People found it very difficult. The unwieldy nature of 
        the tool interfered with their ability to express ideas. With the pencil 
        and brick for contrast, he effectively asked two questions: &quot;What 
        made the difference?&quot; and, &quot;How can we move further in the other 
        direction?&quot;[<a href="#f2">2</a>] This experiment showed people how 
        important their tools and their media were to their effectiveness, and 
        helped them start to see the next brick to remove. 
      <p>Karl Marx performed a similar experiment on society over the course of 
        most of this century. The origin on Figure 16.2 represents where we are 
        now. Karl Marx tied a very large brick to a very large pencil and the 
        last few years have revealed the result to be far worse than the even 
        his harshest critics imagined.[<a href="#f3">3</a>] What made the difference 
        between the societies? Two important elements were open markets and open 
        media. How can we move farther in the other direction? In this presentation, 
        I will be addressing the nature of open media, how they differ from closed 
        media, and how social hypertext systems can enhance the advantages of 
        those media. Applying information technologies to the further opening 
        of markets is left as a mission for the reader. 
      <h3>16.2 Media matter</h3>
      <p>Media matter, because it is in media that the knowledge of society evolves. 
        The health of the process by which that knowledge evolves is critical 
        to the way society changes. Karl Popper, the epistemologist, had the insight 
        that knowledge evolves by a process of variation, replication, and selection, 
        much as biology does. &quot;Variation of knowledge&quot; is what we call 
        &quot;conjecture&quot;--hypothesis formation, tossing new ideas out there. 
        &quot;Replication of knowledge&quot; is the spread of ideas through publication 
        and conversation. &quot;Selection of knowledge&quot; is the discrediting 
        of conjectures through the process of criticism.[<a href="#f4">4</a>] 
        The ability of our knowledge to progress over time depends on an ongoing 
        process of criticism, and criticism of criticism. The ideas that survive 
        the critical process tend, in general, to be better than those that do 
        not. 
      <p>In closed societies, when arguments cannot be spoken, hard truths cannot 
        be figured out. When people cannot openly criticize, cannot openly defend 
        against criticism, or cannot openly propose ideas that conflict with the 
        official truths, then they are left with mistrust and cynicism as their 
        only defense. This leads to the simple heuristic of assuming the official 
        truth is always wrong. For example, because <i>science </i>was promoted 
        by the Soviet propaganda machine, pseudo-science is on the rise in Russia. 
        Because anti-Nazism was promoted by the East German propaganda machine, 
        Neo-Nazism is on the rise in East Germany. The official truth is neither 
        always right nor always wrong. Society needs a more sophisticated process 
        for judging claims. 
      <p>Our society does have open media. Are we in the best of all possible 
        worlds? Are our media good enough? Can they be made significantly better? 
        Among our media, TV is so bad that it is a joke. Only slogan-sized ideas 
        can be expressed. We prize the quality of discourse in our books and journals, 
        but critical discussions in them are only loosely connected. Starting 
        from the expression of an idea, it is hard to find articles that criticize 
        that idea. When arguments cannot be found and navigated, the next harder 
        truths <i>still </i>cannot be figured out. 
      <h3>16.3 Xanadu</h3>
      <p>I rejoined Xanadu in 1988 largely because of fear about the dangers of 
        nanotechnology, coupled with incredible excitement about the promises 
        of nanotechnology. In looking at the dangers, I saw that none of us individually 
        is clever enough to figure out how to solve those problems. The only hope 
        that I saw in 1988--1 no longer believe it is the only hope--is that by 
        creating better media for the process of societal discourse and societal 
        decision-making, we 
      <p>stand a much better chance of surviving the dangers posed by new technologies, 
        so that we may live to enjoy their benefits. 
      <p>I am about to go through the elements of the hypertext system we built. 
        Xanadu has frequently been called Golden Vaporware, and many people have 
        wondered whether this is a never-ending project. One of the things I want 
        to emphasize when I go through all of these features is that I am only 
        referring to the features that are now running in the software. We planned 
        on and anticipate other features, some of which will be mentioned in the 
        <i>future plans </i>discussion, but the body of this presentation will 
        only cover what is implemented and running. 
      <p>First, I will discuss the four fundamental features--links, transclusion, 
        versioning, and detectors. Marc Stiegler will then present an example 
        using them. Then, I will describe the remaining four features--permissions, 
        reputation-based filtering, multimedia, and external transclusion, followed 
        by some concluding remarks. 
      <h3>16.4 Links</h3>
      <p>Hypertext links are directly inspired by literary practice. Literature 
        has many different kinds of links connecting documents into a vast web. 
        Textual examples of these links include bibliographical references, marginal 
        notes, quotation, footnotes, and Post-it notes. 
      <p>We propose to build engines of citation, so that people can navigate 
        this vast web of literature at the click of a mouse. Most computer text 
        systems are predicated on a misconception that the meaning of a document 
        is represented purely or primarily by its content. Documents are not islands. 
        Conventional computer text systems put their effort into the appearance 
        of individual documents. My experience in reading documents (especially 
        reading a literature with which I am not familiar) is that it is difficult 
        to understand documents without their context. A conte~t helps answer 
        questions such as, &quot;What were the ongoing controversies that the 
        author had in mind?&quot; &quot;What views was he supporting or attacking?&quot; 
        &quot;What attacks was he guarding against?&quot; We must understand this 
        whole web of connections in order to understand the documents we are reading. 
        The Xanadu system is built to provide as much support for this contextual 
        information as for content. 
      <p>With the ability to follow the links in this vast web of documents, is 
        it not easy to get lost? How does one stay oriented? One answer to these 
        questions is <i>guides, </i>a new kind of document that provides an orienting 
        view together with links into the existing literature. I expect guides 
        to come largely from people making their own organizing views of a literature 
        and then cleaning them up for publication, so others may benefit from 
        their work. 
      <h3>16.5 Hyperlinks</h3>
      <p>Because &quot;nanotechnology&quot; is now used by many to mean any technology 
        approaching the nanometer scale, we have been forced to retreat to the 
        term &quot;molecular nanotechnology.&quot; Hypertext terminology has gone 
        through a drift similar to nanotech terminology. The Xanadu project is 
        the one that coined the term &quot;hypertext&quot; and originated the 
        notion of the hypertext &quot;link.&quot; However, because the term <i>link 
        </i>has come to be viewed as something much less capable than what we 
        meant by it, we are now calling it the <i>hyperlink. </i>The distinction 
        between the link and the hyperlink is crucial for supporting active criticism 
        in open media. 
      <p>Hyperlinks are fine-grained, bidirectional, and extrinsic. Frequently, 
        an argument is not with a document or chapter as a whole. It is with a 
        particular point that someone made at a particular place in the text. 
        For example, someone refers to the fourth law of thermodynamics, and someone 
        else writes a criticism saying there is no fourth law of thermodynamics, 
        linking it to the original (see Figure 16.3). The fine-grained property 
        allows the link to designate the particular piece of text with which one 
        is taking issue. Bidirectionality enables readers of the original document 
        to find the criticism, enabling them to exercise fine-grained skepticism, 
        and to constantly ask themselves, &quot;What is the best argument against 
        the thing I am reading <i>right now?&quot; </i>and then, &quot;What is 
        the best argument against that, in turn?&quot; Links provided by other 
        hypertext systems generally have been only in the forward direction, enabling 
        a reader to find those documents <i>referenced by </i>a given document. 
        However, to find criticism, the reader must find the documents that <i>refer 
        to </i>the document they are reading. 
      <p>Extrinsic linking is the ability to link into a document without editing 
        it. Several other systems support the creation of links that are fine-grained 
        at the targeted end, but these others do so only by modifying both source 
        and <i>target </i>documents.[<a href="#f5">5</a>] Critics normally will 
        not have the ability to modify the documents they are criticizing. They 
        could spin off their own version into which they attach these links, but 
        then other readers <i>still </i>cannot find these criticisms from the 
        original documents. 
      <p>Part of what we mean by &quot;open media&quot; is that everyone who is 
        connected to the system can read what they are permitted to read, can 
        write new things, and can make them accessible for others to read. This 
        includes making links to anything that they have read, so that anyone 
        else who reads the original can find the material that has been linked 
        to it. All readers of the system are potential authors. We can think of 
        this process as <i>active reading. </i>Frequently, people make marginal 
        notes to themselves. This is a medium in which readers can share such 
        things with each other. When much writing is commentary about other text, 
        the commented-on text is the best rendezvous point for the authors and 
        readers of commentary to find each other. 
      <h3>16.6 Emergent properties</h3>
      <p>This kind of accessible criticism can provide for decentralized consumer 
        reports. When people post on the system documents that are either products 
        or descriptions of products, customers of those products can post criticisms 
        of them. What did they think of using them? This commentary can guide 
        the purchasing decisions of others.[<a href="#f6">6</a>] 
      <p>A particular capability we are used to in conversation (one that is almost 
        impossible to successfully attain using paper-based literature) is hearing 
        the absence of a good response to an argument. A reader not only can see 
        what the most compelling arguments are against some statement, but also 
        see when there are none, or when all the seemingly compelling arguments 
        have been successfully refuted. Such absences are quite obvious in conversation. 
        Electronic media can make these absences obvious as well, but in a context 
        where the absence will be much more telling, because the missing argument 
        could have come from a much larger audience over a more extended period 
        of time. 
      <p>Other hypertext systems with their unidirectional links reproduce the 
        asymmetry present in our paper-based media--it is much easier to find 
        something that a document cites, than it is to find those documents that 
        cite a given document. One of the effects of this asymmetry in paper media 
        is the pathological division of scholarly fields into disjoint &quot;schools.&quot; 
        Instead of healthy intellectual engagement, debate, and cross-fertilization 
        of ideas, we see a process of increasing inability to communicate between 
        schools, and more preaching to the converted within a school. The terrible 
        irony of attempting scholarship with unidirectional links is that <i>the 
        very attempt to engage in healthy debate across schools accelerates the 
        pathological division process. </i>How does this occur? 
      <p>Let us consider two schools within a discipline. Generally, students 
        within a school see the documents supporting the positions of that school. 
        The students also see criticisms of documents in the other school. Intellectually 
        eager and honest students, seeking to know both sides, occasionally will 
        follow these criticism links forward. The result is that they will see 
        the parts of the other school's literature that is <i>most soundly criticized 
        </i>by their own school, immunizing them more and more against the foreign 
        ideas. With bidirectional links, these students can also find the greatest 
        challenges to their own school. Bidirectional links also enable them to 
        find the <i>most telling criticisms </i>of the ideas they are inclined 
        to accept. 
      <h3>16.7 Transclusion</h3>
      <p>Before there were modem economies, there were many little villages, each 
        with their own little manufacturers having to go through a large amount 
        of the production process themselves. These economies were, therefore, 
        much less productive. An individual baker or shoemaker, for example, would 
        reproduce the same kind of work that was being reproduced in many other 
        villages, and would have to fashion a shoe, not quite from raw materials, 
        but without intermediate goods. In extended economies, people can build 
        on one another's work, and there can be a finer-grained division of labor 
        and knowledge, with better specialization. 
      <p>Now, with respect to literature, authors are frequently faced with the 
        task of re-explaining and Iestating background material that has been 
        explained well elsewhere. If you could just borrow that material, those 
        existing good explanations, and incorporate them (with automatic credit 
        where due), your efforts could be spent stating what is new. We introduce 
        the concept of <i>transclusion </i>to separate the arrangement of a document 
        from its content. There is an underlying shared pool of contents, and 
        all documents are just arrangements of pieces from that pool. In Figure 
        16.4, the three circled appearances of the same text are actually just 
        one piece of text in the underlying shared pool of contents, and it just 
        happens to appear in three different arrangements which constitute three 
        different documents. We refer to the three documents as <i>transcluding 
        </i>that piece of text. The separation of content and arrangement also 
        leads to good support for 
      <p>incremental editing. Different versions of a document are just different 
        arrangements of mostly shared content. 
      <p>This is more than just a hack to avoid the storage cost of making separate 
        copies. Hyperlinks are linked to the content, not to a span in an arrangement. 
        Therefore, when someone writes a criticism of content as it appears in 
        one arrangement, that criticism is visible for the same content as it 
        appears in all other arrangements, including arrangements that were made 
        before the criticism was attached. The normal incremental editing process 
        of a single document is analogous to <i>evolution by point mutation. </i>The 
        ability to transclude text from other documents allows the analog of sexual 
        recombination. Were links visible only from the arrangement into which 
        they were made, both variation processes would destroy selection pressures 
        by leaving criticisms behind. 
      <h3>16.8 Remembering the past: historical trails</h3>
      <p>As you are editing, an <i>historical trail </i>gets left behind--bread 
        crumbs in history space. The historical trail is simply a sequential arrangement 
        of the successive arrangements of contents. This is yet another kind of 
        context important for understanding. &quot;Things are the way they are 
        because they got that way.&quot;[<a href="#f7">7</a>] 
      <p>Understanding <i>how </i>they got that way often aids our understanding 
        of what <i>theyare. </i> 
      <h3>16.9 Preparing for the future: detectors</h3>
      <p>In addition to looking into the past, one also reads a literature knowing 
        it will be changing. How can one keep up? To keep track of what is happening, 
        to keep up with changes, we introduce <i>detectors. </i>One can post a 
        <i>revision detector </i>to find out when things are edited, when new 
        versions of something appear, and then one can use <i>version compare 
        </i>to find out how they are different. With version compare, one can 
        engage in <i>differential reading--</i>reading<i> </i>just the differences 
        between the current version and the version most recently read. 
      <p><i>Link detectors </i>are a way of finding out when new links are made 
        to existing material. Let us say that you published something, and you 
        want to find out when others post comments on it. You would like to be 
        informed of comments, but you do not want to have to go back and constantly 
        Iecheck all the things that you have written, so you post a link detector 
        on all the things that you have written, as well as on other documents 
        on which you are interested in seeing further comments. You want to see 
        what people will say about them. As new comments are posted on those documents, 
        you are continually informed. 
      <p>E-mail is just the special case where you establish a canonical point 
        in the literature, for each person--a place others link to in order to 
        send that person a message. That person simply has a link detector there 
        saying, &quot;Show me all new things that are attached to <i>here.&quot; 
        </i>This generalizes to treating any shared point of interest in the literature, 
        as in some sense, a &quot;mailbox,&quot; or a &quot;meeting room&quot; 
        for further conversation or conferencing about a topic. Canonical documents 
        become meeting places. Should two disjoint discussions about the same 
        topic spontaneously form in two places, anyone who notices can just make 
        a link between them. The link detectors of each community will then inform 
        them of the existence of the other. 
      <p>At this point, 1 will shift over to Mark Stiegler and Dean Tribble, who 
        will demonstrate, using the Xanadu software, an example involving exactly 
        the elements discussed so far. 
      <h3>16.10 The WidgetPerfect saga</h3>
      <p>This is a true story about how a hypertext system was able to save several 
        thousand jobs, One special characteristic about this true story is that 
        it is a true story from the year 1997. It is a story about one of the 
        events that took place at the company--most of you have heard of it--called 
        WidgetPerfect. WidgetPerfect is the second largest manufacturer of widgets 
        in the world, second only to their 
      <p>big competitor, Microwidget. The people at WidgetPerfect in the year 
        1997 had identified a xeally significant opportunity in the upcoming expanding 
        environment of widget components technology. 
      <p>They were developing the world's first fully modular widget. They had 
        a team working on it. Dan was in charge of the preparation of the marketing 
        materials for the modular widget. Ruth was in charge of the technical 
        work team, and John was in charge of the budget and finance, as well as 
        all the costing. At this point, the modular widget was in prototype stage 
        when a very unfortunate thing happened. Microwidget, the big competitor, 
        came out with a partially modular widget, hitting the marketplace first 
        with an inferior product. It was technically inferior, but nonetheless 
        it was in the marketplace first. 
      <p>Dan was examining this Microwidget, partially modular widget, and it 
        was overall inferior. Nonetheless, it had one really striking improved 
        feature. It had a funculator made out of titanalum, whereas the fully 
        modular widget that was being developed by Ruth only had a duralum funculator. 
        This was an important improvement for certain key market sectors. Even 
        though the partially modular widget did not have anything comparable to 
        a thermoplastic coupler or a hypervelocity rotator, they had to make a 
        change. 
      <p>So, Dan created a new document in the marketing requirements describing 
        this titanalum funculator. He attached a link to the part of the technical 
        plan that specifically referred to the duralum funculator in the current 
        plan. He made that a new requirement (see Figure 16.5). 
      <p>Now, Dan knew that in order to get anything to happen with improving 
        the widget prototype, he would have to talk to Ruth. He was reaching for 
        the telephone to call Ruth when Boeing, the largest purchaser of widgets 
        in the world, called him about a $15 million widget order. He got distracted 
        with this purchase, and he never quite got around to calling Ruth. 
      <p>We have good news. Ruth, knowing that the success of her technical design 
        depended on her being able to respond promptly to new requirements, had 
        attached a link detector to her technical plan. This link detector would 
        be constantly watching for new links of the link-type <i>requirement </i>to 
        be attached. When Dan attached the new requirement to the duralum funculator, 
        Ruth's link detector went off. Ruth was alerted. She followed the link 
        detector out to the link, followed the link back to the new requirement, 
        saw what the required change was, and modified the technical plan to reflect 
        the use of a titanalum funculator. 
      <p>Well, this was all very fine, except for an additional problem. As I 
        think everyone here knows, titanalum is considerably more expensive than 
        duralum, and so this had some significant effect on the manufacturing 
        cost. Ruth knew that this would have an impact on the budget, and she 
        was reaching for the telephone to call John when smoke started billowing 
        from the laboratory where the 
      <p>prototype of the modular widget was being manufactured. She ran off to 
        deal with the emergency and never quite got around to calling John. 
      <p>We have good news. John, knowing the success of his budget was completely 
        dependent on his responding to modifications to the technical plan, had 
        attached a revision detector to the technical plan and this detector was 
        constantly watching for updates. So, when the technical plan was indeed 
        updated, John's revision detector went 
      <p>off. He followed the revision detector up to the technical plan, used 
        the hypertextual version compare capabilities based on the transclusion 
        relations, compared the new version of the plan to the old, and found 
        that the change was deleting duralum and replacing it with titanalum. 
        He then went back into the budget and updated the budget documents to 
        reflect the increased costs caused by the use of titanalum. 
      <p>As a consequence of this, the modular widget program was completed on 
        time with a fully adequate specification. It was a completely superior 
        product. It blew Microwidget off the face of the Earth. As a consequence, 
        thousands of jobs at WidgetPerfect were saved. 
      <h3>16.11 Permissions</h3>
      <p>A social system, to a large extent, is a system of rights and responsibilities. 
        Xanadu has an extensive permission system called the <i>club </i>system, 
        intended to deal with some of these issues. Figure 16.6 shows a document 
        that Bob can edit. Bob has sent it as a mail message to various people 
        in a blind carbon copy (&quot;bcc&quot;) relationship. Alice and Chuck 
        are both members of the <i>bcc </i>club of people who have permission 
        to read this document. Bob, though, is the only member who can read or 
        edit the <i>bcc </i>club. If this were a <i>cc </i>list, Bob would still 
        be the only person who could edit it, but it would be self-reading. Everybody 
        who was a member of such a <i>cc </i>club could see who else was a member 
        of that same club. 
      <p>This demonstrates a principled answer to permissions <i>meta-issues--0ne 
        </i>can distinguish between who can read a document, who can read the 
        list of people who can read a document, and who can read that list, out 
        to any desired degree of distinction (and similarly for the editing dimension). 
        However, infinite regress and needless complexity are avoided by using 
        clubs that are self-reading or self-editing (or both) whenever further 
        distinction is currently not necessary. Should such distinction later 
        become necessary, it can always be introduced by someone with appropriate 
        edit permission to the club in question. Users only grow meta-Ievels on 
        an as-needed basis. 
      <p>Our permission system also supports the notion of <i>accountability. 
        </i>All actions in the system are taken <i>by someone. </i>When you look 
        at information in the system, you see some identity attached to the actions 
        taken on the information. There are no official truths. There is only 
        who said what, and the structure of the system reflects that. 
      <h3>16.12 Reputation-based filtering</h3>
      <p>One of the potential pitfalls of an open hypertext system is the junk 
        problem. The ability to find good commentary and crit~cism will be especially 
        important 
      <p>when reading very important documents, but it is precisely on <i>these 
        </i>documents that one expects to be inundated with tons of worthless 
        or irrelevant links. Without a filtering mechanism, it would be on exactly 
        the documents for which one most needs good commentary that the provision 
        of commentary would be most useless. For example, imagine how many links 
        there would be onto the First Amendment to the Constitution. 
      <p>Links can be <i>endorsed </i>as worth reading by various readers. However, 
        no 
      <p>one may endorse with the identity of another. Different endorsers will 
        establish varying reputations with different readers, much as with movie 
        reviewers. Readers can filter their views of links into a document both 
        by <i>who </i>endorsed as well as by link-type. When even this mechanism 
        gives too coarse an answer, one can rely on documents such as a hypothetical 
        <i>Guide to the Citations to the Bill of Rights, </i>endorsed by a reputable 
        publishing house. This very same link filtering ability is also what allows 
        one to find such guides in the presence of a swamp of links. 
      <h3>16.13 Hypertext + multimedia = hypermedia</h3>
      <p>Increasingly, ideas are being expressed in media other than text, and 
        increasingly, computers are used to handle these other media. We usually 
        refer to <i>hypertext </i>because text is the most important case and 
        the clearest example. However, nothing I have presented, none of the things 
        you have seen the system do, is in any way specific to text, or even to 
        media that have linear flow to them. It all applies equally well to a 
        variety of other media (such as sound, engineering drawings, Postscript 
        images, and compressed video). In all cases, one can make fine-grained 
        links, edits, transclusions, and version compares ( even if the data is 
        block-compressed or block-encrypted). Although the implementation has 
        some optimizations targeted at text, in no way does the <i>architecture 
        </i>make any special cases for text. Documents can, of course, be composite 
        arrangements in which several media are mixed together. 
      <h3>16.14 External transclusion</h3>
      <p>No software system is an island. We do not imagine that once the product 
        is available, everyone will instantly take all information to which they 
        want access and transfer it into Xanadu. We have to coexist with many 
        other systems for many good reasons. 
      <p>We handle that with <i>external transclusion. </i>Our documents are able 
        to transclude into anangements that are within the system. These, in turn, 
        are able to represent transclusions of materials that are stored elsewhere. 
        By perceiving other systems through the window of Xanadu, you can see 
        those other systems as if all those documents were within the Xanadu system. 
        Through Xanadu, I could follow a link from a WAIS document into a Lexis 
        document, even though neither system has any notion that such a link even 
        exists. It is not just that the Xanadu system is not an island, that we 
        have to coexist with everything else, it is that through Xanadu, <i>those 
        </i>systems are able to coexist with each other in a way they are unable 
        to now, making <i>them </i>into nonislands. 
      <h3>16.15 Conclusions</h3>
      <p>When we started building the system, we were thinking purely in terms 
        of paper-based literature-of writing. What we have built is something 
        that has many of the best aspects of both writing and conversation (see 
        Table 16.1). Many of the aspects of each are complementary. Many virtues 
        of conversation make up for flaws in writing and vice versa. We found 
        ourselves building a system that supports the dynamic give-and-take of 
        conversation, and the persistence and thoughtfulness of literature. 
      <p>Our status is that we currently have a working, portable server. It has 
        some bugs in it, including some performance bugs, but we are working on 
        it. However, all the features that I talked about so far, work. We are 
        continuing ahead with the effort on both the server and the front end. 
        The front end is in a preliminary stage. We consider it adequate to show 
        that the server is real, and to exercise its features. We plan to do a 
        much better front end. The protocol between the front end and the server 
        is very stable, and has been stable for a long time now. Our plans are 
        to get investors, and to finish both the front end and the server. The 
        target for our first product is small- to medium-sized workgroups within 
        companies that have a large body of documents they need to be managing 
        and evolving. 
      <p>Our first product lacks one major feature. We provide hypertext because 
        documents are not islands. We make the system interpersonal because people 
        are not islands. We provide for the transparent windowing into other systems 
        because no product is an island. However, for the moment, each server 
        is still an island with respect to the other servers, and so each workgroup 
        is also an island. We have designed the system so that, soon after first 
        product, we will be able to weave all the servers together into a transparent 
        distributed system. When you follow a link from one document to another, 
        if the other document is not here but in some server in Tokyo, it will 
        be transparently fetched for you, and the only thing you will notice is 
        that following that link took longer. 
      <p>For any media to radically improve the process of opinion formation in 
        society, we believe it <i>needs </i>features equivalent to fine-grained, 
        bidirectional, extrinsic, filtered links. These links must not get lost 
        when the documents to which they are attached change. Issues of authority, 
        privacy, and responsibility must be handled in a robust and secure fashion. 
        Open entry of readers and editors is crucial for open discussion. Open 
        entry of server providers is less obvious, but equally important, in order 
        to make centralized control impossible. We will be providing support for 
        people who want to do online services based on our software. All of this 
        is necessary to achieve our open electronic publishing dream. In so doing, 
        we hope to improve the quality of public debate, in order to obtain the 
        benefits of the open society yet again. 
      <h3>16.16 Acknowledgments</h3>
      <p>We thank the whole extended Xanadu team for having struggled together 
        for many years on a project that has been at least as much a cause as 
        a business. We thank Eric Drexler for exploring the relationship of hypertext 
        publishing to evolutionary epistemology.[<a href="#f8">8</a>] We thank 
        Anita Shreve for extensive help in editing this presentation. 
      <p> 
      <h3>Footnotes</h3>
      <p><a name="f1"></a>[1] The <b>Xanadu <sup>TM</sup></b> trademark has since 
        become the sole property of Ted Nelson. 
      <p><a name="f2"></a>[2] Engelbart, D. C., &quot;<b>Augmenting Human Intellect: 
        A Conceptual Framework</b>,&quot; <i>SRI Project </i>no.3578, October 
        1962. 
      <p><a name="f3"></a>[3] Popper, K. R. <i><b>The Open Society and its Enemies</b>. 
        </i>(Princeton, N.J.: Princeton University Press, 1950) 
      <p><a name="f4"></a>[4] Karl Popper originally proposed that selection proceeds 
        by a process of refutation. See Sir Karl R. Popper, <i>The Logic of Scientific 
        Discovery </i>(New York: Harper &amp; Row, 1959). His student, William 
        Bartley, generalized this to criticism. See William W. Bartley, III, <i><b>The 
        Retreat to Commitment</b> </i>(Open Court Publishing, 1962). 
      <p><a name="f5"></a>[5] Examples include World Wide Web <i>anchors, </i>Microsoft 
        Word <i>bookmarks, </i>Lotus Notes, and Folio Views <i>Popup text. </i> 
      <p><a name="f6"></a>[6] The use of bidirectional links for decentralized 
        consumer reports is already happening on the <b>American Infonnation Exchange</b>. 
      <p><a name="f7"></a>[7] Weinberg, G. M., <i><b>The Secrets of Consulting</b> 
        </i>(Dorset House Publishing, 1985) 
      <p><a name="f8"></a>[8] Drexler, K. E., &quot;<b>Hypertext Publishing and 
        the Evolution of Knowledge</b>,&quot; <i>Social Intelligence. </i>1 (1991): 
        Number 2. 
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