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Chapter3: A Perspective on the Quest for Global Knowledge Interchange

Steven R. Newcomb

Edited by Jongnam Kim

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Table of Contents

Information Is Interesting Stuff Information and structure Are Inseparable Formal Languages Are Easier to Compute Than Natural

Languages Generic Markup Makes Natural Languages More Formal A Brief History of the Topic Maps Paradigm Data and Metadata:

The Resource-Centric View Subjects and Data:

The Subject-Centric View Understanding Sophisticated Markup Vocabularies The Topic Maps Attitude Summary

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Information Is Interesting Stuff (1/2)

Relationship Between information and the material universe (reality) Mineral-ness <--> Mineral

Influenced the design of the topic maps paradigm

?

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Information Is Interesting Stuff (2/2)

The topic maps paradigm recognizes, adapts itself to, and exploits this chasm

Universe of Information

Universe of Subjects

Human Intuition

chasm

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Information and structure Are Inseparable

Natural languages == “unstructured” ?

Even the simplest kind of information has a sequence Beginning, middle, end Concept of Unit, hierarchical levels

No such thing as “unstructured information”

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Formal Languages Are Easier to Compute Than Natural Languages

Formal Language Expressively impoverished language Involving everything that computers

do You are unfamiliar with formal

languages? Dialing a telephone number Web addresses

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Generic Markup Makes Natural Languages More Formal (1/3)

XML, like SGML, allows users to define their own markup vocabularies

“How can global knowledge interchange be supported?” interchangeable info = sequence of char Key: standard and user-specifiable

Predominance of SGML and XML Notion of generic markup, as opposed to

procedural markup

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Generic Markup Makes Natural Languages More Formal (2/3)

Procedural markup

<italics>Command Center</italics>

Helpful for a rendering application But, useless for supporting applications that are

looking for occurrences of the names of building

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Generic Markup Makes Natural Languages More Formal (3/3)

Generic markup

<building-name>bunker</building-name>

Says, “The next characters are the name of a building,”

Generic tag can support many more kinds of applications

Information-oriented, not application-oriented

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A Brief History of the Topic Maps Paradigm (1/2)

Began in 1991 by Davenport Group Need to be able to merge indexes

ISO/IEC 13250 Topics and relationships between topics Relationship -> association Facet, scope (key feature of TM)

Biezunski’s Principle “There is no point in creating a standard

that nobody can understand” <topic> element type – totally unnecessary,

but got a popularity

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A Brief History of the Topic Maps Paradigm (2/2)

ISO 13250 standard Finalized in 1999 Published in January 2000

TopicMaps.Org creating & publishing an XTM 1.0 spec Core of the XTM 1.0 spec

XML 2000 conference in Washington, DC, on December 4, 2000,

Final version of XTM 1.0 on March 2, 2001

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Data and Metadata: The Resource-Centric View

Metadata Being “in orbit” around the data

Ironically more and more information inaccessible Sheer quantity of it (“infoglut”)

Search engines Metadata web sites

Categorization of information resources Metametadata, Metametametadata…

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Subjects and Data:The Subject-Centric View

Platonic forms Underlying layer

Subject Hub around which data resources can orbit

Resource-centric view Metadata orbits data resources

Subject-centric view Data orbits subjects

Problem Computers cannot access subjects unless those

subjects happen to be information resources themselves

Communicate symbolically

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Example

‘Starcraft’ Information Space

Mineral 400

scan 50

love Medic

“Additional SupplyDepot is required.”

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Understanding Sophisticated Markup Vocabularies

In 1986, SGML had just adopted as the one-and –only markup language for everything

Problem of representing music abstractly Musical works are multidimensional

Currently, regard XML as an opportunity to represent relational databases as interchangeable documents

Document Object Model (DOM) Only provide direct access to the syntactic

components of how a document is represented for interchange

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The Topic Maps Attitude

A step along the road to global knowledge interchange

Will owe much of its success to the fact that it is responsive to current

technological, economic, and anthropological conditions,

and just as responsive to certain philosophical values and attitudes

Comparatively young traditions of the markup languages community

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Summary

Topic maps provide us with two different and important views into an information space Resource-centric view

Use metadata to describe the resources we reference with topics

Subject-centric view Topic maps provide the tools necessary to

represent, to “talk about” subjects