Sunday, August 26, 2007

Professor Victor Raskin's Talk

This past Friday (8/24/07) Professor Raskin of Purdue University and Hakia gave a talk at the New York Semantic Web Meetup What follows is a summary of Raskin's points and my own thoughts on the topic.

Summary Of Key Points

  • Conceptually, the Semantic Web (SW) is a good and noble vision.
  • The present proposal for the SW by Tim Berners-Lee (et. al.) will fail.
    • Formalisms like OWL don't capture meaning. Tagging is not representation of meaning (shallow semantics = no semantics).
    • The average web author (or even above average) is not skilled enough to tag properly. Semantics requires well-trained ontologists.
    • Manually tagging can be used to deceive search engines.
  • Formalisms, in and of themselves, are useless. The meaning of the formalism is what counts.
  • Ontology (like steal-making) is something that requires highly skilled practitioners. Ontology is not for the masses.
    • Most computer scientists know next to nothing about language or semantics.
    • Statistical and syntactic techniques are useless if one is after meaning.
    • Native speakers are experts in using their language but are highly ignorant about their language (i.e., how language works).
  • Meaning is language independent, so even though ontologies use symbols that look like words, they are really tokens for language-independent concepts.
  • Raskin's Ontologic formalism is called Text Meaning Representation (TMR).
  • TMR uses a frame like construct where the slots store case roles, constraints and other information like style modality, references, etc. (See
  • The Semantic Web does not need OWL or any other tagged based system because web authors will not need to tag once a full Ontological Model (and other related tools, like lexicons, semantic parsers, etc.) are available.
    • Ontological Search Engine will be able to index pages by meaning without the help of web authors.
    • This is what Hakia is working on.
My Impressions of the Presentation

Professor Raskin is a very good presenter with a unique and humorous style (think of a cross between Jackie Mason, David Letterman and Albert Einstein). His points resonated well with my own impressions of the present architecture and direction of the Semantic Web. However, I thought that his presentation was too unbalanced. There were far too many slides critical of the SW and Tim Berners-Lee, in particular and far too little on Ontological Semantics.

My Thoughts on Raskin's Points

  • I could not agree more with Raskin on the inadequacy of the present architecture of the SW.
  • I also believe it is primarily the job of automated software tools to extract semantic information. However, I think web authors could help these tools be more efficient. My earlier post speaks to this point somewhat but after hearing Raskin's presentation, I plan to refine these thoughts in a future post.
  • Raskin's point on the difficulty of "the masses" creating ontologies does not bode well for my vision of a Wisdi. However I am not the least bit discouraged by his bias toward expertly trained ontologists.
    • Pre-Linux, experts in operating systems would have claimed that a commercial grade operating system could never be constructed by a loose band of programmer-enthusiasts.
    • Pre-Wikipedia, intellectuals would have thumbed their nose at the idea of a competitive encyclopedia being authored by "the masses".
    • The success of these projects stem from three major ingredients:
      1. The involvement of some expert individuals
      2. The involvement of many many enthusiastic but not necessarily expert participants.
      3. Unending rounds of testing and refinement (ala Agile Methods and Extreme Programming).
  • So I believe that a Wisdi model can ultimately kill an elitist approach because the elitist-expert approach can get too expensive. Information, knowledge and meaning do not remain static so ontologies must change and grow to remain relevant. I think an open collaborative approach is a good model for this endeavor. If you agree, I'd love to hear from you (flames equally welcome!).


Ontological Semantics Book

The Whys and Hows of Ontological Semantics

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