A Plague o' Both Our Houses?

Topic Maps and the Semantic Web
Introducing RDFTM
http://www.w3.org/2001/sw/BestPractices/RDFTM/

 

Steve Pepper

Chief Strategy Officer, Ontopia

<pepper@ontopia.net>

Steve Pepper – "The Topic Maps guy"

• Convenor of the ISO Topic Maps committee
  • ISO/IEC JTC 1/SC 34/WG 3
    http://www.isotopicmaps.org/
  • Editor of XML Topic Maps 1.0 (XTM)
    http://www.topicmaps.org/xtm/1.0/
  • Author of The TAO of Topic Maps
    http://www.ontopia.net/topicmaps/materials/tao.html

Ontopia – "The Topic Maps Company"

• Long term interest in the relationship between RDF and Topic Maps
  • Pepper: Ten theses on Topic Maps and RDF (June 2000)
    http://www.ontopia.net/topicmaps/materials/rdf.html
  • Garshol: Living with Topic Maps and RDF (May 2003)
    http://www.ontopia.net/topicmaps/materials/tmrdf.html
  • Pepper/Schwab: Curing the Web's Identity Crisis (May 2003)
    http://www.ontopia.net/topicmaps/materials/identitycrisis.html
• Joined W3C in October 2004 at the instigation of Eric Miller to work on RDF/Topic Maps interoperability

"Two households, both alike in dignity..."

• During the late 1990s the W3C and ISO developed two semantic technologies in parallel
• Two communities, largely unaware of each other
• Tackling the same fundamental problems
  • Findability ("Where's my stuff?")
  • Semantic interoperability ("How do I connect my stuff?")
• The results were RDF and Topic Maps

RDF and Topic Maps have many similarities...

• Both "extend" XML into the realm of semantics
• Both allow assertions to be made about subjects in the outside world
• Both define abstract, associative (graph-based) models
• Both are very concerned with identity
• Both allow some measure of inferencing or reasoning
• Both have XML-based interchange syntaxes
• Both have constraint languages and query languages

...and this naturally led to calls for unification

• Extreme Markup 2000:
  • "Free-for-all" between The Two Erics (Miller and Freese)
• Michael Sperberg-McQueen:
  • "Lock them in a room together until they agree!"
• Easier said than done, because...

There are also significant differences...

• Different roots
  • Topic Maps: Traditional finding aids (indexes, thesauri, etc.)
  • RDF: Document metadata and formal logic
• Different levels of semantics
  • RDF is more low level
  • Topic Maps has more higher-level semantics

More differences...

• Different models (down in the details)
  • Identity, scope, association roles, n-ary relationships, variant names, ...
• Different goals
  • RDF: An artificially intelligent web for software agents
  • Topic Maps: Findability and knowledge integration for humans
• So unification never happened
  • Some interesting work was done...
  • But the perception of rivalry is still causing damage

Time to move beyond rivalry

• Let's look for the synergies instead!
  • Both families have user communities
  • Neither standard will go away anytime soon
  • Common interest in the success of semantic technologies
  • Semantics are hard enough to explain to the market as it is
  • A standards war will indeed lead to a Plague o' Both Our Houses...
• RDF and Topic Maps are different
  • Different strengths, different weaknesses
  • Let's recognize this
  • And let's go for interoperability
• That's the goal of RDFTM...

RDFTM: "What's in a name?"

• RDF/Topic Maps Interoperability Task Force
  • A task force within the SemWeb Best Practices Working Group
• Chartered to deliver two documents:
  • Survey of Existing Interoperability Proposals (WG Note)
    • First draft of Survey recently delivered to WG
      http://www.w3.org/2001/sw/BestPractices/RDFTM/survey
  • Guidelines for RDFTM Interoperability (WG Note or Recommendation)
    • First draft of Guidelines for Extreme Markup 2005
      http://www.extrememarkup.org/
• Only five years late, Michael :-)
• Interested parties, please join us!

"Parting is such sweet sorrow"

Questions?