SUO: Re: General Design
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John,
Okay, so let's put purposes (Greek 'pragmata') back in
as explict parameters of all the 2-adic relations that
we normally try to represent, ending up with relations
like these:
A is better than B for the purpose C.
X is subsumed by Y with respect to Z.
and so on ...
Now, I dearly love lattices, posets, preorders as much as
anybody has a right to, but they are all 2-adic relations,
and so there's just gonna have to be some threads hanging
loose when you try to pack up sign relations or any other
3-adics in your lattices. It's the conservation of arity.
Jon Awbrey
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John F. Sowa wrote:
>
> Dear Matthew,
>
> Thank you for the support. I have been arguing for
> as long as the SUO list existed that every engineering
> project (including knowledge engineering) makes
> abstractions from reality that omit seemingly
> "irrelevant" details. But what is irrelevant for
> one project is often the central core of some
> other project.
>
> I certainly agree with people like Adam, Doug, and
> Nicola that axioms are essential for detailed reasoning.
> But in the early stages of any design -- and in any
> stage of communication between independent projects --
> conflicts in the assumptions (i.e., the axioms) are
> the major obstacle. And you simply *cannot* solve
> that problem by forcing people to adopt axioms that
> weren't designed for their purpose.
>
> Of all the axioms that have been proposed, the
> axioms of mereology are the worst offenders.
> I consider mereology to be a useful approximation
> for many purposes, but those axioms are *always*
> approximations that are simply false at the level
> of atoms and molecules (and even at the level of
> bacteria, dust, surface grime, and cat hairs).
>
> That is why I consider any ontology with lots of
> formally defined axioms -- including Cyc, Sumo,
> and Dolce -- to be at best a useful approximation
> for some purposes, and at worst a disaster waiting
> to happen for other purposes.
>
> That doesn't mean that we have to throw away all the
> work that went into writing the axioms of Cyc, Sumo,
> and Dolce. But what we must do is to develop means
> of modularizing them and, for any given purpose,
> extracting, combining, and revising whatever modules
> are appropriate.
>
> John
>
> PS: Note how many times the word "purpose" occurs in
> the above paragraphs. Some people have been trying to
> eliminate the idea of "purpose" from their ontologies.
> That attempt is guaranteed to make their work useless
> for *every* purpose.
> _____________________________________________________
>
> West, Matthew R SITI-ITPSIE wrote:
>
> > Dear John,
> >
> > A word of support.
> >
> > > Of course, not. The main reason why WordNet is more flexible than
> > > Cyc, Sumo, Dolce, or any other axiomatized ontology is simple;
> >>
> >> The axioms get in the way.
> >
> > I have spent many years trying to improve the quality of data models
> > in Shell and elsewhere. By far the biggest problem has been that
> > data models impose constraints that simply aren't true (except in
> > some limited set of circumstances). As a result I have become very
> > conservative about constraints or axioms.
> >
> > Matthew West
> > Principal Consultant
> > Shell Information Technology International Limited
> > Shell Centre, London SE1 7NA, United Kingdom
> >
> > Tel: +44 20 7934 4490 Other Tel: +44 7796 336538
> > Email: matthew.west@shell.com
> > Internet: http://www.shell.com
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