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-----Original Message-----
From: pat hayes [mailto:phayes@ai.uwf.edu]
Sent: Monday, August 27, 2001 5:24 PM
To: Adam Pease
Cc: standard-upper-ontology@ieee.org
Subject: RE: RE: SUO: Re: Ballot CommentDo you feel a change is needed to axioms about Physical <http://ontology.teknowledge.com:8080/rsigma/SKB.jsp?req=SC&skb=Merge-WordNet&id=95>?
(documentation Physical "An entity that has a location in space-time. Note that points of space and time are themselves understood to have a
location in space-time")
Can someone elucidate this second sentence? For example, consider the north pole, which we can take to be a point in space. Does that point have a time? Rotating the axes, does a timepoint (eg 3:02 pm PDT on 21 August 2001) have a spatial location? Or is this supposed to be saying that *spatiotemporal* points are spatiotemporally located? (Note, time points and space points are not spatiotemporal points: they are respectively 3-d slices and 1-d timelines in a 4-d ontology.)
> Joe has a left arm.
> Joe had a left arm at age 10.
> Joe had a left arm at age 20.
> Is Joe's arm at age 10 the same object as Joe's arm at age 20?
> A 3d view says yes.
> A 4d view says no.
MW: Well yes and no. In the first place 4D is tenseless. A 4D view of
Joe's arm is that it is that spatio-temporal extent that operates
as Joe's arm throughout his life. This allows for the changing
material composition of his arm over time. The whole spatio-temporal
extent is made up of states of those cells/molecules/atoms whilst
they were part of his arm.
MW: So the equivalent question to ask is whether the temporal part of
Joe's arm when he was 10 (this can be a time slice or a period) and
when he was 20 are temporal parts of his whole-life arm.
MW: Then the answer is "yes".
MW: On the other hand, the time slice of his arm at 10 is not the same
object as the time slice of his arm at 20. Notice I am still tenseless.
If I understand you correctly, then you may be closer to the current SUMO representation than I thought. Here's a formalization in SUMO:
(instance JoesArm OrganicObject)
(instance JoesArmAtAge10 OrganicObject)
(instance JoesArmAtAge20 OrganicObject)
This is wrong in the endurantist framework, which would reject JoesArmAtAge10 as a meaningful object (it doesn't endure).
(spatioTemporalPart JoesArmAtAge10 JoesArm)
(spatioTemporalPart JoesArmAtAge20 JoesArm)
(equal (BeginFn JoesArmAtAge10) (BeginFn (YearFn 1990)))
(equal (EndFn JoesArmAtAge10) (EndFn (YearFn 1990)))
(equal (BeginFn JoesArmAtAge20) (BeginFn (YearFn 2000)))
(equal (EndFn JoesArmAtAge20) (EndFn (YearFn 2000)))
The key then is in the definition of a new relation for SUMO which we could call 'spatioTemporalPart' which would allow us to deduce
(not (equal JoesArmAtAge10 JoesArmAtAge20))
Now, at the danger of pointing out a flaw in this, we'd have to assume that no one who wants to use a 3d viewpoint would ever want to reify temporal sub-parts. Because from the above formalization, they'd want to conclude
(equal JoesArmAtAge10 JoesArmAtAge20)
I'm hoping though that this might be an acceptable compromise in terms of practical modelling support.
Congratulations, you have just reinvented the 4-d ontology. At least, I think you have. Notice that all these are timeless assertions, as Matthew requires, but which would be meaningless in an endurantist (3-d) framework. So is SUMO solidly tense-free, and rejects all talk of 'ordinary' objects as lasting through time, retaining their identity as they last? What other relations hold between JoesArm and JoesArmAtAge10?
BTW, don't you think it might be better to introduce an interval-slicing function, so you can write
(At JoesArm (YearFn 1990)) rather than JoesArmAtAge10, which has no more relationship to JoesArm than to Xyyzz as far as the logic is concerned? Then you could *quantify* over timeslices of things, which is very handy, eg you could write
(equal (BeginFn (At ?x?y)) (BeginFn ?y))
which kind of sums up a lot of stuff. See "Naive Physics I: Liquids" in J.R. Hobbs and R.C. Moore (Eds.) Formal Theories of the Common Sense World (Vol. 1). Norwood, NJ: Ablex Publishing Company, 1985 for some more examples.
Pat
Adam
>
> The practical issue is that each view has merit in different
> situations so
> how do we create a formalism that allows us to express facts
> in either
> viewpoint and yet map between them in a way that doesn't
> result in some
> inconsistency.
>
> Is this an accurate assessment?
MW: This looks about right. 4D needs a tighter set concept, and something
like spatio-temporal-extent as starter objects under the structural and
set theory work of Chris M. 4D classes are different from 3D classes,
but we could construct a superset of equivalent concepts. Processes map
quite simply - they might even be the same object (but I wouldn't want
to assume that yet). Continuants of course do not exist in a 4D
ontology, and we would have to define a mapping to a whole-life
spatio-temporal extent.
MW: A lot of axioms would look somewhat different - mostly simpler
because time is already built in.
>
> Adam
>
>
> >X-Sender: apease@ks.teknowledge.com
> >X-Mailer: QUALCOMM Windows Eudora Version 5.1
> >Date: Thu, 23 Aug 2001 10:06:49 -0700
> >To: "West, Matthew R SITI-GREA-UK" <Matthew.R.West@is.shell.com>,
> > "'pat hayes'" <phayes@ai.uwf.edu>
> >From: Adam Pease <apease@ks.teknowledge.com>
> >Subject: RE: SUO: Re: Ballot Comment
> >Cc: standard-upper-ontology@ieee.org
> >Sender: owner-standard-upper-ontology@majordomo.ieee.org
> >Reply-To: Adam Pease <apease@ks.teknowledge.com>
> >X-Resent-To: Multiple Recipients
> <standard-upper-ontology@majordomo.ieee.org>
> >X-Info: [Un]Subscribe requests to majordomo@majordomo.ieee.org
> >X-Moderator-Address:
> standard-upper-ontology-approval@majordomo.ieee.org
> >
> >
> >Matthew,
> > Comments below:
> >
> >At 09:11 AM 8/22/2001 +0200, West, Matthew R SITI-GREA-UK wrote:
> >>Dear Adam,
> >>
> >>Let me collect the critical bits and dump the rest.
> >>
> >>
> >>
> >> > >MW: Where did I say it is impossible? I am saying something
> >> > >about our current knowledge, not about what is possible.
> >> >
> >> > Pat has been quite forceful in asserting that we can't
> come up with a
> >> > single consistent ontology. Some other folks have also
> >> > asserted that we
> >> > shouldn't be working on creating a single ontology. Maybe I
> >> > responded too
> >> > strongly as to your position. One message in which you
> appear to say
> >> > this(aggreeing with Pat, my emphasis in '*') is
> >> >
> >> >
> >> > >From: "West, Matthew MR SSI-GREA-UK"
> <Matthew.R.West@is.shell.com>
> >> > >
> >> > >MW: However, I don't think I would want to argue for a 4D
> >> > view INSTEAD OF a
> >> > >continuant/occurrent view, or a Piercean view (which I take
> >> > to be different
> >> > >again - subject to correction by John). Rather I think we
> >> > should develop
> >> > >each and relate them to each other, rather than the current
> >> > process of
> >> > >trying to merge them into one.
> >> > >
> >> > >MW: Pat said some time ago that it is probably ***not
> >> > possible*** to merge
> >> > >them,
> >> > >and most of the discussion since has been convincing me he
> >> > is right. Equally
> >> > >people clearly do use different metaphysical paradigms in
> >> > developing various
> >> > >ontologies, and I doubt if that is about to stop, what ever
> >> > we do here, so
> >> > >relating these different paradigms would be a general
> >> > service (and we might
> >> > >learn something).
> >> >
> >>
> >>MW: OK fundamental principles/beliefs first.
> >>
> >>1. We live in a world/universe that is what it is. In theory
> >>it is possible to create a model/ontology that mirrors it.
> >>Therefore a single ontology is possible (theoretically).
> >>
> >>2. Our knowledge of the world is incomplete. In practice we
> >>have a number of different views of the world that are limited
> >>and each is probably useful for particular purposes.
> >>
> >>3. Some of these views are compatible, some are not. E.g. 3D/4D
> >>as above, or wave and particle theories of light.
> >>
> >> > [snip]
> >> >
> >> > > > Let's say that we do fail to
> >> > > > come up with a
> >> > > > single consistent ontology, then we'll wind up with a set,
> >> > > > plus a clear
> >> > > > understanding of what the real incompatibilities are.
> >> > >
> >> > >MW: Yes, but the current merging process transforms as well
> >> > >as incorporates the source material. This can both miss and
> >> > >mask incompatilibities.
> >> >
> >> > The position I would take however is that the merging process
> >> > is evaluating
> >> > and then correcting any incompatibilities. If there is
> a specific
> >> > incompatibility in the SUMO proposal (i.e. axioms that allow
> >> > us to deduce
> >> > both P and (not P)) we'd love to have that pointed out.
> >>
> >>MW: But you have not incorporated valid alternative views.
> For example
> >>you have no 4D view of the world in the SUMO. You have selected 3D
> >>and that's it. I don't think you can merge a 4D and 3D view. You can
> >>only have them as alternatives, with perhaps a (partial)
> mapping in between.
> >
> >The definition of Process
> ><http://ontology.teknowledge.com:8080/rsigma/SKB.jsp?req=SC&n
ame=Process&caseSensitive=on&skb=Merge-WordNet>
> >does allow for Object(s)
> ><http://ontology.teknowledge.com:8080/rsigma/SKB.jsp?req=SC&s> kb=Merge-WordNet&id=51>
> >to be participants in the process. I don't think 3d and 4d are
> >necessarily as incompatible as you assert them to be, but
> let's work it out.
> >
> >Maybe we can work this through concretely. Let's come up with some
> >statements in English and I'll try to formalize them. Then
> we'll have
> >three possible outcomes
> >
> >1. I'll show how they can be modeled with terms from SUMO
> >2. we'll find that there is some error or gap in SUMO and
> we'll add the
> >appropriate definitions
> >3. we'll find that there is a genuine incompatibility
> between the two
> >paradigms that can't be bridged, and we'll define precisely
> the logical
> >forms that are incompatible.
> >
> >>MW: The issue is not so much one of consistency (both P and
> (not P)) as
> >>accuracy
> >>- does the ontology reflect how the world/universe is, and
> over what range
> >>is it a good reflection. 3D and 4D ontologies operate over
> different,
> >>overlapping ranges.
> >>
> >>MW: You could argue that doing this would make them part of
> one ontology,
> >>and I would agree to some degree. However, I think it is
> more useful to
> >>see them as different ontologies with mappings, largely for
> the reasons that
> >>John puts forward.
> >
> >If we really do find that they can't be mapped to each
> other, then I'll be
> >happy to have the outcome that we define two different
> theories that can
> >be plugged into the rest of SUMO.
> >
> >Adam
> >
> >>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.r.west@is.shell.com
> >>Internet: http://www.shell.com
> >>http://www.matthew-west.org.uk
> >
> >Adam Pease
> >Teknowledge
> >(650) 424-0500 x571
>
> Adam Pease
> Teknowledge
> (650) 424-0500 x571
>
Adam Pease
Teknowledge
(650) 424-0500 x571
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phayes@ai.uwf.edu http://www.coginst.uwf.edu/~phayes