Re: SUO: Re: SUO Comment #3
Bill,
I think what this objective says is that while using the SUO in
implementations that support expressive languages is the way to get the
full usefulness out of the standard, the SUO is still useful for
implementations that use less expressive languages. A reasonable analogy
might be to using design tools and methodologies for object oriented
programming. If you have RationalRose and have defined mapping preference
in Rose for how UML constructs are to be translated to Java code, you get
the full benefit of modeling work in assisting your
implementation. However, even if you do UML modeling in a drawing tool
like Visio and just write English comments for your classes and methods,
you still gain significant benefits for your implementation.
In the same way, even though a software developer would have to ensure
compatibility of the semantics of his or her Java procedures with the
formal semantics of terms specified in the SUO, he or she would still
derive a benefit from intended compatibility between implemented (albeit
less expressive) code and the SUO.
Adam
At 02:49 PM 8/15/2000 -0400, Bill Andersen wrote:
>"West, Matthew MR SSI-GPEA-UK" wrote:
> >
> > Dear Bill,
> >
> > I don't think it is as bad as you make out.
> >
> > As far as I can see, conformance to the SUO means using the terms of
> the SUO
> > with the meaning of the formal definition defined by the SUO in the SUO
> > language.
>
> Right... But that might not (probably won't) be possible even in
>principle in the case of RDF, for example, which doesn't even admit
>negation. The compilation target system has to be capable of the
>semantic expressiveness of the SUO language. Perhaps there are W3C-
>like proposals for XML-based languages of this sort, but I'm not
>aware of them. We're talking pretty much full FOL for the SUO lang-
>uage and all of the XML-based languages being considered for popular
>use come nowhere close in expressiveness. That means approximation
>will be required. As Mike Uschold commented, he doesn't see this
>approximation as that much of a problem, but it's still a problem.
>
> > So there is no problem if someone does just strip out the terms and use
> > them, provided the use conforms to the formal definition (if it didn't it
> > would be non compliant, and that is something you could check against the
> > formal definition, albeit that not being available directly).
>
> Concrete example - We're likely to have a disjointness relation
>between types in the SUO. This is pretty standard fare. So you
>write it like this:
>
> (forall (P Q)
> (<=> (disjoint P Q)
> (forall (x)
> (<=> (P x) (not (Q x))))))
>
> where P, Q range over unary predicates.
>
> How do you do this in RDF-like language (without negation) without
>resorting to a definition outside the language itself? Alternatively
>one could build such functions one by one as special cases inside the
>language (like a Lisp special form) but then SUO users are obligated
>to cope with these without guarantee that compiling a particular
>subject ontology to different target languages A and B will result in
>two implementations that are able to communicate in a meaningful way.
>
> ...bill
-----------------
Adam Pease
Teknowledge
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