[sc34wg3] SAM-issue psi-generics (was: SAM-issue term-scope-def)

[Bernard Vatant]

Marc

I would not like to make this thread endless, since I think we've drifted from original
subject ... This is one last attempt to make me understood ... after that I think we
should continue this interesting debate off this forum before being kicked off by Lars
Marius :))

> I understand your point of view but I find the discontinuity you allow
> between topics and subjects very strange. For the topic 'Marc' you would
> allow two characteristic assignments:
> - 'Marc' is an instance of class topic
> - 'Marc' plays husband-role in marriage X (in which Y plays wife-role)

The first one has not to be declared explicitly. When you work in set theory, "set-ness"
of every set you use is not declared ...

> Now you do agree that I - the person - am not a topic, and you would
> probably agree I am married to Y (at least if you had been present at the
> occasion).

No, "you" are not married to topic Y - I hope so.
Topic 'Marc' and topic 'Y' and their association are in the model

> So there are two quite different kinds of assertions you allow on
> a topic: those that have a counterpart in the real world (the husband role)
> and those that have no counterpart in the real world (the topicness). I
> think that is going to be pretty confusing for a user browsing the Topic
> Map. That person is simply going to see a couple of class-instance
> relationships when she clicks on topic 'Marc':
> - 'Marc' is a 'husband'
> - 'Marc' is a 'topic'
> (or something similar).

> How is this Topic Map user going to know that I - the person - am a husband
> but not a topic???

This is just a question of interface, not a question of model. Depends on what you call
"browse the Topic Map", and what the interface looks like. The fact that 'Marc' is a Topic
could appear implicitly in the interface, through specific display, icon, color, font,
whatever ... whereas other characteristics will appear otherwise. And, as a matter of
fact, in many interfaces the user will/should not know that there is a topic map under the
hood anyway.

> Your view is consistent, but Lars' view seems much simpler: we only allow
> topic characteristic assignments which express facts about the subject the
> topic represents.

I wonder how you could put that in a model. I don't know what are "facts about the subject
the topic represents", and I would not dare propose a definition of that, but it is
clearly out of the model.

> Well, yes and no. In the Topic Map itself the subjects won't appear, but in
> a standard like SAM it makes sense to say something about the relation
> between the Topic Map and the subjects.

"A topic represents a subject". Full stop. All the rest is metaphysics.

> Maybe maths, but certainly not physics (and most other sciences). There you
> look at the real world, make a model, compute a bit to make predictions, and
> go back to the real world to do experiments and see if the predictions from
> the model fit reality.

Not that simple. You look at the real world through two filtering layers, the information
you can get and its interpretation. And you don't test a model in physics against
*reality*, but against *interpretation of information you get from experiments*, which is
quite different. The information that you get, you interpret in terms of subjects.
Subjects live at this interpretation level, not in the real world. And those subjects are
represented in the model by formal objects like topics, vectors, numbers, fields, whatever
...

> So the interpretation in terms of subjects plays an
> important role in physics.

Yes, indeed, *in terms of subjects*. I'm happy that Nikita agrees with me there. He's been
dealing with very arcane "subjects" in Physics, namely neutrinos, and it is indeed a field
where distinction between model, subjects, and "real world" is really tricky if any, and
where distinction between experiment and interpretation of experiments is crucial ... You
never actually "see" or "handle" a neutrino, you interpret very elusive events in pools
deep under the mountains as the signal of interaction of some "thing" you have imagined
and called a neutrino to speak about it, and of which "reality" is certainly more strongly
established in the mind and models of physicists than in the "real world" ... the *concept
of neutrino* is a subject if any ... a neutrino itself, well, does it "exist"?

Go ask Nikita ...

Bernard

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Bernard Vatant
Consultant - Mondeca
www.mondeca.com
Chair - OASIS TM PubSubj Technical Committee
www.oasis-open.org/committees/tm-pubsubj/
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