XML provides scaffolding for linking document trails

In section 7 of Vannevar Bush’s 1945 Atlantic Monthly article “As We May Think” (see www.theatlantic.com/unbound/flashbks/computer/bushf.htm), Bush talked about “a new profession of trail blazers, those who find delight in the task of establishing useful trails through the enormous mass of the common record. The inheritance from the master becomes, not only his additions to the world’s record, but for his disciples the entire scaffolding by which they were erected.”

Even in 1945, it could be argued that this might not have been a new profession since in “The American Scholar” address to the Phi Beta Kappa Society at Cambridge in 1837 (see www.jjnet.com/emerson/amscholar.htm), Ralph Waldo Emerson observed that “the office of the scholar is to cheer, to raise, and to guide men by showing them facts amidst appearances. He plies the slow, unhonored, and unpaid task of observation.”

In my earliest writings about computer conferencing, I observed people called “porters,” who appeared spontaneously and delighted in porting what they thought were “useful discussions” from one conference to another. I observed that in general, humans spend a lot of time focusing on two complementary tasks: connecting every living human to all other living humans and connecting every living human to the collected knowledge of all humans who have ever lived.

Buckminster Fuller went further in Critical Path to suggest that the role of humans, and what made them unique in the universe, was that of information gatherer/processor in support of the ever regenerative universe.

Bush’s “Vannevar Trail” or VT as described in my last column ( CWC, July 28, 2000, page 16) is thus a mechanism for building this scaffold or showing facts amidst appearances. It is not a mere bibliography or annotated bibliography or even links from the scholars document to others. It is, as Vannevar Bush describes it, a named collection of links, separate from the documents it references, each link connecting two or more documents or resources, with no requirement to modify the documents being referenced.

One XML technology that can implement a VT is called XLink (see article entitled “Links That Are More Valuable Than the Information They Link” at www.xml.com/pub/98/07/xlink/index.html). The introduction to this candidate recommendation indicates that support is provided for both basic unidirectional links – like the HTML A element – and more complex linking structures called extended links.

According to the article, “It allows XML documents to: assert linking relationships among more than two resources, associate metadata with a link and express links that reside in a location separate from the linked resources.”

Thus it is the “extended link” that provides the necessary underpinnings for a VT. In a future column, I will examine the extended link functionality more closely.

Chatfield, ISP, is president of CyberSpace Industries 2000 Inc. in Ottawa. He is engaged in XML/SGML consulting and teaching, and can be reached at hchatfie@attcanada.ca.