SUO: Re: SUO Comment #3
"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