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RE: erratum ... RE: allValuesFrom and rdfs:domain

From: Bernard Vatant <bernard.vatant@mondeca.com>
Date: Fri, 19 Dec 2003 10:26:30 +0100
To: "Nikita Ogievetsky" <nogievet@cogx.com>, "'Www-Rdf-Logic@W3. Org'" <www-rdf-logic@w3.org>
Message-ID: <GOEIKOOAMJONEFCANOKCMEDPCOAA.bernard.vatant@mondeca.com>


Nikita

> ! There are so many possible definitions for a blue thing. Yours would be
> ! good for Klein's "Monochrom Blue". Sorry, I don't buy those.
>
> Sorry, I was not selling anything, just tried to help.

Thanks :))

> Knowing just an id of "BlueThing" was not sufficient enough to
> understand what you mean.

Well, "I" don't mean anything. I've no definitive idea of what a Blue Thing
can be, or even if the concept of a Blue Thing is relevant at all. You know
my complete agnosticism about the real world, since we had long discussions
about it. I was just putting on the table various possible formal
definitions, all of them sensible, and trying to figure the entailments.

> So I gave you a suggestion that you
> can modify as you wish to fit definition of "BlueThing" that you have in
mind.

Yes, of course - supposing I have something precise in mind - which is not
the case, actually. My mind is sort of fuzzy, that's why I need some sort
of external representation ...

> Note though that "someValuesFrom" assumes
> at least on value. So "InvisibleThing" is not included.

Sure. If you have at least one "color" value you are visible - assuming the
given definition of the domain of "color" being VisibleThing, of course.

> (Unless you start complaining that you meant invisible a la Magritte "The
> Invisible World"
> http://www.the-artfile.com/uk/artists/magritte/invisibleworld.htm
> which is actually quite blue according to your latter definition of
> "BlueThing")

I sure would buy that one, if I could afford it.

> Consider a fading "BlueThing" eventually it becomes invisible. But at any
> moment it is still blue. So there is nothing wrong with an
> ontology where InvisibleThing is a BlueThing.

Yes, indeed. I was more thinking about some hidden stuff, like Shrodinger's
cat. You don't know if it is alive or dead, but you don't know its color
either. It has a certain probability of being blue until you open the box
...

> In fact keeping definition of colors that you originally proposed
> InvisibleThing is an intersection of BlueThing, RedThing and GreenThing.

Well, I'm not sure it's the intersection, but it contains instances of all
of those, sure.

> When you reply please consider the fact that I do not know what
> you mean by colored things and "*Thing"-s in general.

Please consider that *I* mean nothing, as said above. Only the formal
representation pretends to mean something. At least that's what logicians
pretend when they speak about semantics. There are folks much more
knowledgeable than me about it lurking on this list :))

Best

Bernard
Received on Friday, 19 December 2003 04:26:43 GMT

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