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Re: White Paper - "Using OWL to Avoid Syntactic Rigor Mortis"

From: Roger L. Costello <costello@mitre.org>
Date: Thu, 17 Apr 2003 14:31:19 -0400
Message-ID: <3E9EF2F7.3881C792@mitre.org>
To: www-rdf-interest@w3.org
CC: "Costello,Roger L." <costello@mitre.org>

Baoshi Yan wrote:
> 
> It seems the white paper makes a remise that different users would follow the same OWL ontolgy, and they
> are only allowed to use the different terminologies *predefined* in the ontology. How can you foresee all different kinds
> of terminologies that could possibly be used?

I am juggling this discussion on two different lists.  I just answered
this question on the other list, so I will simply copy and paste here. 
Sorry that it's not a personalized response (it takes a lot of time to
answer all the comments!).  Here is my response:

An Ontology may evolve in a distributed fashion (just like the Web
itself!)

For example, suppose that when I build my application the Camera
Ontology only defines these terms:

   Camera, aperture, (lens) size

I then construct my application to understand physical expressions (XML
instance documents) which uses these terms.  Now, suppose that time
passes and the Camera Ontology evolves to include these additional
terms:

   SLR, f-stop, focal-length

Further, these relationships are specified in the Ontology:

   "SLR is a type of Camera"
   "f-stop is synonymous with aperture"
   "focal-length is synonymous with (lens) size"

Now, without any modifications to my application, I can process this
physical expression:

<SLR>
   <optics>
       <Lens>
           <f-stop>...</f-stop>
           <focal-length>...</focal-length>
       </Lens>
   </optics>
   <shutter-speed>...</shutter-speed>
<SLR>

How are this be?  After all, it is using terms (SLR, f-stop, and
focal-length) that my application was not constructed to understand. 
Well, when my application encounters a term that it does not understand
it "consults" the Camera ontology:

   "What do you know about SLR?"

The Ontology returns:

   "SLR is a subclassOf of Camera"

My application understands:

   - "subclassOf" since it's part of the OWL vocabulary
   - "Camera" since my application was constructed to understand this

So, my application now understands that this physical expression is
talking about Cameras.  Further, it is talking about a particular type
of Camera.  

Thus, without a-priori agreement my application is able to process a
trading partner's document!  /Roger
Received on Thursday, 17 April 2003 14:31:32 GMT

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