The Semantics of Semantics
Dmitry Gaivoronsky
http://johndcyc.blogspot.com/2006/04/semantics-of-semantics.html
===
*The Semantics of Semantics*
_Bill_ [http://www.cs.utexas.edu/~billj/] _Jarrold_
[http://www.ai.sri.com/people/jarrold/] of _SRI_ [http://www.sri.com/] sent me
some comments about my presentation on the 13th (see below), and I'd like to
respond. He said the presentation was pretty good, but noted:
-+-
Some people will differ with your characterization that OWL contains no
semantics. People are working on adding rules to OWL and OWL-Full is quite
descriptive. OWL-DL is much weaker, but is computationally pretty good
(description logics run in polynomial time). But, in spirit, you are right.
From what little I know, Tim Berners Lee seems to urge everyone to keep moving,
that through common use we will eventually arise at some sort of folksonomy
like effect.
-+-
Okay, I want to clarify what I meant when I was talking about Semantic Web
standards.
With regard to representing the meaning in documents, I made the claim that,
despite a number of new W3C standards, we're in the same situation as we were
with Electronic Data Interchange (EDI) 20 years ago. That's not true. The W3C
standards are actually a huge advance over EDI (by which I really mean _X12_
[http://www.x12.org/]). Currently, however, they don't aim to deal with the
issue of a common vocabulary that (within the business domain) EDI focused on
for 25 years. There is nothing inherent in the W3C standards that keeps us from
taking that extra step, so I'm excited that the Cyc Foundation will be able to
offer a part of the solution to that issue.
People often talk about the Semantic Web by comparing "syntax" to "semantics."
I divide the knowledge representation problem into syntax, vocabulary, ontology
and semantics (as defined in my previous blog post). It's not completely
accurate, but accuracy can be the enemy of clarity sometimes. :-)
OWL has support for semantics. OWL-Full has a quite a bit more support for
semantics than OWL-DL. Neither contains a lot of meaning about things in the
world, because the intention is to rely on ontologies expressed in OWL. It is
up to users of OWL to add the meaningful terms that depend on the semantics
that OWL provides.
As a result, we have a proliferation of ontologies from which, it is hoped, a
common set of meaningful terms will emerge. At this point, there is some
meaning in each of the ontologies, but there is not a shared meaning across
ontologies.
I'm going to save discussion of folksonomies and emergent semantics for another
post. For now, suffice it to say: I don't oppose ground-up development of
ontologies, and there is no inherent contradiction between doing that and
having a unifying hub ontology. I look forward to working with the OWL
community in creating a sustainable, semantically rich Web.
posted by #$JohnD @ 9:52 PM Saturday, April 15, 2006
0 comments
===
Sayonara... Dmitry.