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Re: Do resources have representations?

From: Norman Walsh <Norman.Walsh@Sun.COM>
Date: Mon, 28 Jul 2003 11:53:14 -0400
To: www-rdf-interest@w3.org
Message-ID: <87r84afy1h.fsf@nwalsh.com>

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/ Benja Fallenstein <b.fallenstein@gmx.de> was heard to say:
[...]
| OWL specifies that if A owl:sameIndividualAs B, then all statements
| you can make about A entail a similar statement about B. E.g., if I say
|
|      <http://example.com/EveningStar>  rdf:type  foo:BeautifulThing
|
| then I'm implying that
|
|      <http://example.com/Venus>   rdf:type   foo:BeautifulThing
|
| I think that implying it is basically as good as saying it, so I think
| that it's not useful to say that the two statements are specific to a
| particular intension of the thing described, because if I make one of
| the statements, I also make the other (in RDF+OWL).
|
| What do you think?

I think you can make assertions until the cows come home and their
veracity will always be independent of the representation that you get
back if you perform a retrieval operation on a particular URI with a
particular request.

I assert that <http://norman.walsh.name/knows/who#norman-walsh> is me.
I also assert that <http://norman.walsh.name/knows/what#flower-coreopsis>
is a coreopsis. You believe those assertions at your own peril.

Now, as chance would have it, those assertions are in fact true. And
as the authority for the norman.walsh.name domain, I have pretty much
the last word on the subject.

But that doesn't prevent you from asserting that <http://example.org/people/ndw>
is me and making RDF assertions with that URI.

The assertions you make may or may not be true. The extent to which
Joe Random User believes our respective assertions will depend on
many factors. Joe may retrieve the URIs and change his opinion about
which statements he believes. Or he may meet me on the street and I
may tell him that he can trust you and he may change his opinion about
which statements he believes.

There's no magic here. If you do a GET and get back some RDF, you can
choose to believe it or not. If you do a GET and get back a PNG, I
don't know what you can do with that. But just because you got RDF
yesterday and PNG today offers no guarantee about what you'll get
tomorrow.

                                        Be seeing you,
                                          norm

- -- 
Norman.Walsh@Sun.COM    | A child becomes an adult when he realizes he
XML Standards Architect | has a right not only to be right but also to
Web Tech. and Standards | be wrong.--Thomas Szasz
Sun Microsystems, Inc.  | 
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Received on Monday, 28 July 2003 11:53:43 GMT

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