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RE: [ontac-forum] What should be in an upper-level ontology

To: "ONTAC-WG General Discussion" <ontac-forum@xxxxxxxxxxxxxx>
Cc: "Lenat, Doug" <doug@xxxxxxx>
From: "West, Matthew R SIPC-DFD/321" <matthew.west@xxxxxxxxx>
Date: Mon, 22 May 2006 08:55:18 +0100
Message-id: <A94B3B171A49A4448F0CEEB458AA661F032BBDC4@xxxxxxxxxxxxxxxxxxxxxxxxxxxx>
Dear John,    (01)

Well this at least I can broadly agree with.    (02)

The main thing I would note is that you are starting with an 
assumption that an Upper Ontology is/should be. You are assuming
it should be that which should common regardless of any ontological
commitments one might choose to make. This of course fits with
you ideas for a "Lattice of Theories" (which again I support).    (03)

I also think that some sort of cleaned up version of Wordnet can
be incorporated into this. But considerable care is needed here.
Let us take person (or more generally organism). You need to be
careful not to say it is a subclass of physical object or process,
both, or even that there might be two organisms (organism as physical
object, and organism as process). Equally, we can all agree (I hope)
that there are people (whatever they are). I don't know how you can 
leave yourself that uncommitted (can you explain how to do that?)    (04)

This is pretty much the position I was trying to take with Pat
before the Upper Ontology Summit. I would agree this could be
called THE Common Upper Ontology, but I think it is different from
what Pat has in mind.    (05)

However, I think there is another interpretation of Upper Ontology
which says that it is enough to specify the key ontological commitments
for an ontology. So precisely whether it is 3D, 3+1D or 4D. Whether/when
the vase and clay are the same object, etc.    (06)

I guess in your terms these would be top level micro-theories, and 
if we can agree on a Lattice-of-Theories approach, then this would 
fit well. I would still call these Upper Ontologies however (as
opposed to THE Common Upper Ontology).    (07)

I think that it would be very interesting to pursue what could be a
Common Upper Ontology. I agree with you that it would be surprising
how much had to be left out, even at the subtype/supertype level.    (08)


Regards    (09)

Matthew West
Reference Data Architecture and Standards Manager
Shell International Petroleum Company Limited
Shell Centre, London SE1 7NA, United Kingdom    (010)

Tel: +44 20 7934 4490 Mobile: +44 7796 336538
Email: matthew.west@xxxxxxxxx
http://www.shell.com
http://www.matthew-west.org.uk/    (011)


> -----Original Message-----
> From: ontac-forum-bounces@xxxxxxxxxxxxxx
> [mailto:ontac-forum-bounces@xxxxxxxxxxxxxx]On Behalf Of John F. Sowa
> Sent: 21 May 2006 18:56
> To: ONTAC-WG General Discussion
> Cc: Lenat, Doug
> Subject: [ontac-forum] What should be in an upper-level ontology
> 
> 
> Folks,
> 
> I have been making some strong criticisms about upper-level
> ontologies, even though I have been working on and writing
> about such things for many years.
> 
> I haven't completely given up on the idea that an upper level
> is useful, but over the years, I have come to the conclusion
> that any upper level should be as *neutral* as possible --
> i.e., it should not be biased for or against anybody's pet
> theories, and it should not contain any axioms that contradict
> any of the specialized axioms that anybody might need in any
> application at any lower level.
> 
> These criteria imply that the upper levels should have very
> few axioms.  Following are some kinds of axioms that should
> *not* be in the upper levels:
> 
>   1. Any axioms that make empirical claims that might be
>      falsified by future experiments or any claims that are
>      known to be false in detail, but which may be useful
>      approximations for many purposes.  For example, the upper
>      levels should be neutral with respect to a Newtonian view
>      vs. any more modern theory of physics because for many
>      practical purposes a Newtonian description is accurate
>      within the granularity of the usual measuring instruments.
> 
>   2. Any axioms that require, prefer, or rule out one kind of
>      representation over another, such as a four dimensional
>      vs. a (3+1) dimensional description of space and time.
> 
>   3. Any axioms that rule out exceptional cases that may be rare,
>      but possible.  For example, it should not say that a tiger
>      has four legs, because some tigers might be born with more
>      than four and some might lose a leg.  In fact, there might
>      be quadriplegic tigers that get around in some prosthetic
>      device.
> 
>   4. Any axioms that imply a vase and the clay it consists of
>      are or are not identical, because many respectable theories
>      make different claims in that regard.  They should also
>      avoid all claims about whether a child is identical or not
>      identical to the adult at some later stage of life -- because
>      some theories say yes, others say no, and other treat the
>      question as context-dependent (i.e., identical for inheritance
>      issues, but not identical for employment).  In fact, the
>      entire issue of identity claims is so full of conflicting
>      philosophical positions that the upper levels should *not*
>      make any identity claims of any kind.
> 
>   5. Any axioms that imply physical objects and processes are
>      disjoint.  Some theories say they must be disjoint, others
>      say they may overlap, and others say that object and process
>      descriptions are complementary ways of describing the same
>      phenomena.
> 
>   6. Any axioms about artifacts that may be falsified by developments
>      in technology.  For example, the attached phone.gif example is
>      taken from a dictionary published in 1969, but very few of the
>      features depicted are common in the telephones manufactured
>      today.  However, the definition in that dictionary is still
>      true:  "an instrument for reproducing sounds at a distance."
> 
>   7. Any axioms that distinguish essential properties from accidental
>      properties.  This issue has been debated since the time of Plato
>      and Aristotle.  The traditional definition of Human is Rational
>      Animal, and the ability to laugh was considered an accidental
>      property.  However, many philosophers have claimed that the
>      ability to laugh is just as characteristic of humans and more
>      easily defined than the ability to reason.  Today, genes are
>      considered more fundamental to what is "essential", but that
>      makes it harder to distinguish humans from chimps and bonobos.
>      A truly neutral upper level should avoid any commitment to what
>      is considered essential vs. what is considered accidental.
> 
> When you start to analyze the issue, the number of possible conflicts
> becomes so large, that the safest position with regard to any axiom
> in the upper levels is very short:  When in doubt, leave it out.
> 
> That definition of telephone from 1969, which is still true today,
> suggests the kind of information that might be included in an upper
> level:  a definition or axiom that is true because of the intended
> function of an artifact.  Unfortunately, it is very difficult to
> state such definitions in full generality and even more difficult
> to find formally defined relations that can be used to state them.
> 
> For example, how can the words "instrument", "reproduce", "sound",
> and "distance" be defined in a precise, but general way?  And how
> could they be defined in a way that would distinguish a telephone
> from a radio?  And would you want to distinguish telephones from
> radios?  If you did, that would rule out cell phones, which are
> in fact radios and can be used to reproduce radio programs and
> even television programs.  In fact, cell phones are now being used
> as cameras and even TV cameras that broadcast live events over the
> Internet.
> 
> If you want the upper levels to be sufficiently general, you can't
> put many axioms into them.  They become, in fact, just what I said
> in my previous notes:  a cleaned-up version of WordNet.  It's not
> an accident that WordNet is so widely used, because it performs a
> needed function.  Anything that is more detailed than WordNet would
> be too constrained and too inflexible to be useful for relating
> one general-purpose ontology to another.
> 
> For deduction, however, inflexibility and constraints are necessary
> to support detailed proofs.  But those constraints will inevitably
> create contradictions with very important developments in technology.
> If you define the word "telephone" in such a way that makes 
> it disjoint
> with radios, TVs, and cameras, then you rule out cell phones -- or
> perhaps you may permit very simple cell phones, but you rule out any
> kind of new technology without making a major category shift.
> 
> Summary:  When you examine all the conditions and applications that
> an upper-level ontology must serve, you discover that it is very hard
> to distinguish it from a cleaned up terminology.  It is clear that we
> need detailed axioms in the microtheories, but it is not at all clear
> whether we need an upper level that is distinct from a terminology.
> 
> John Sowa
> 
>     (012)


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