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Re: [ontolog-forum] Webby objects

To: ontolog-forum@xxxxxxxxxxxxxxxx
From: John F Sowa <sowa@xxxxxxxxxxx>
Date: Fri, 16 Nov 2012 13:34:00 -0500
Message-id: <50A68718.8010201@xxxxxxxxxxx>
On 11/15/2012 5:47 PM, Pat Hayes wrote:
> I am as a matter of policy ignoring all rants about how
> almost everyone got almost everything wrong...    (01)

Pat, you are listed in one of the 22 groups that participated in DAML.
My opinions are based on the original proposal, some interim reports,
the final report, and various later documents.  I defer to you on
any questions about what happened in that project.    (02)

But that list also includes people as diverse as Roger Schank and
Doug Lenat.  Tim's proposal [1] is sufficiently broad that the people
on the list [2] could support it.  But I can't believe that all or
even a majority of them would concur with the final report [3] and
the subsequent developments.  Silence is not consent.    (03)

All my rants about the Semantic Web stem from two basic points:    (04)

  1. Tim Berners-Lee's DAML proposal of February 2000 was mostly right
     about the major issues required for the SW, but it was much more
     ambitious than what could be implemented in five years.  But as
     an outline and goal for the SW, it remains far better than
     anything else that has been written about it.    (05)

  2. The DL aficionados who promoted and enforced decidability pushed
     the SW in a direction that was antithetical to nearly every major
     issue that Tim had hoped to develop.  The slippery slope began
     with OWL (full) from the DAML project, but it went over the cliff
     with the later emphasis on decidability.    (06)

Everything else supports or follows from those two points:    (07)

  1. Three terms that Tim emphasized in the DAML proposal were
     diversity, heterogeneity, and interoperability.  He discussed
     those points and the requirements for supporting them.  He also
     said that trust had to be addressed "early" in the DAML project.    (08)

  2. In the 1990s, the most widely used DL systems were LOOM and
     PowerLOOM.  They were hybrids with a DL for the type hierarchy
     and with lots of features that users needed for application
     development.  Bob MacGrgegor (who was also on the DAML list)
     stated the obvious:  "Users always ask for more expressive
     power, and they never ask for decidability."    (09)

  3. Tim also mentioned a wide range of logics and systems, which
     included KIF, Prolog, and relational databases.  From [1], "the
     Semantic Web must provide a common interchange language bridging
     these diverse systems...  SWeLL (Semantic Web Logic Language)
     will enable this interchange."  SWeLL is the "unifying language
     for classical logic", and the layer cake shows that SWeLL
     includes propositional, first order, and higher order logic.    (010)

  4. In the final DAML report, SWeLL became N3, which is a simpler
     notation for RDF triples, but it also goes beyond RDF in
     expressive power (exactly what power that includes is not
     stated).  But Figure 2, which shows "The Semantic Web Wave",
     puts N3 under the heading "non-web or non-standard".  Even
     worse, SQL, KIF, Prolog, Cyc, and "etc" are in the pre-1998
     "wave" -- legacy systems that don't even reach the level of
     "non-web or non-standard".    (011)

  5. SQL runs the world economy, it's an ISO standard, and it is still
     the primary DB language for commercial web sites.  To claim that
     SQL is "non-web or non-standard" pushes the overwhelming majority
     of commercial web sites outside the scope of the SW.  That is why
     Google, Microsoft, Apple, IBM, and Amazon do not use OWL.  They
     might import RDF, but their tools immediately convert RDF to more
     efficient notations.  For Google, JSON is the notation used by
     all Google apps.  IBM's Watson uses SQL for its DB, it uses Prolog
     for complex AI reasoning, and it uses XML for the UIMA notation,
     not for RDF or OWL.    (012)

  6. In the yearly interim reports for DAML, there were fewer and
     fewer references to Tim's points about diversity, heterogeneity,
     interoperability, and trust.  Diversity and heterogeneity are
     not mentioned in the final DAML report.  Interoperability occurs
     only in the sentence "N3 is used as an interlingua for interoper-
     ability for different systems", but Figure 2 says that N3 is
     "non-web or non-standard".  And trust "continued to exist only
     at the research level."    (013)

  7. The requirement of decidability eliminated heterogeneity and
     diversity.  N3, RuleML, SWIRL, and SWeLL were eliminated.
     PowerLOOM, Cyc, Prolog, and every major programming language
     are undecidable, and their users would never accept anything
     less.  DLs have always been most useful as part of a hybrid
     with more expressive languages.  But the decidability purists
     forced every one of them out of the approved list.    (014)

>> An even better notation would used typed triples, such as
>>    {T1:V1, T2:V2, T3:V3}
>> This could be translated to RDF, but it would expand to five triples.
>> So the type labels often get lost along the way.    (015)

> What?? The Web does not use a "type" to specify what a URI points to.
> URIs are Web addresses in themselves (sometimes a bit more, but
> *at least* a Web address.)    (016)

As Duane N and Doug F have pointed out, the original URLs are primarily
addresses with a bit more information given by the "http" prefix.  Since
the original WWW assumed that the browser's primary goal was to display
whatever occurred at the target of a URL, any descriptors in a document
would tell the browser how to display the content.    (017)

But a reasoning system needs more information about how it should
treat a name.    (018)

> What 'types' are you talking about here?    (019)

Two kinds of information:    (020)

  1. Syntactic information that says some occurrence of a name should
     be treated as a reference to a function, relation, or individual.
     In RDF, it's not clear whether a name refers to a document, to
     its content, or to an operation specified by its content.    (021)

  2. A monadic relation that specifies the ontological category or
     position in a type hierarchy.  In CL, that information can be
     stated in relational form (T1 V1) or in a quantifier restriction.    (022)

______________________________________________________________________    (023)

References    (024)

  1. The original DAML proposal from February 2000:
     http://www.w3.org/2000/01/sw/DevelopmentProposal    (025)

  2. The list of 22 DAML groups and their members:
     http://www.daml.org/researchers.html    (026)

  3. (a) The W3C version of the DAML final report:
     http://www.w3.org/2005/12/31-daml-final.html    (027)

     (b) The official final report as delivered to DARPA:
     http://www.dtic.mil/cgi-bin/GetTRDoc?AD=ADA458366    (028)

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