W3C home > Mailing lists > Public > www-rdf-logic@w3.org > June 2003

Re: Is everything blank?

From: pat hayes <phayes@ai.uwf.edu>
Date: Fri, 6 Jun 2003 09:09:03 -0500
Message-Id: <p0521060dbb064ea6df31@[10.0.100.24]>
To: <jimbobbs@hotmail.com>
Cc: <www-rdf-logic@w3.org>

>  > Not sure what you mean. Certainly, it would be possible to take any
>>  OWL triple (Using Ntriples notation):
>>
>>  ex:foo ex:Property ex:baz
>>
>>  and replace it with
>>
>>  _:x ex:Property ex:baz
>>  _:x owl:sameIndividualAs ex:foo
>>
>>  and the two are equivalent. And since they are, the second form is
>>  kind of confusing (not wrong, but confusing) since one might easily
>>  think, when reading it, why didn't they just write the first one?
>
>I was thinking that a node is some abstract thing, and the name (URI,
>QName, whatever) of a node is a property of the node.

No, that was one way to understand RDF graphs, and it used to be the 
'official' way, but we realized a while ago that there was really no 
need to distinguish between URIrefs and literals and the nodes they 
'labelled', so the official line now is that in these cases the 
URIref or literal *is* the node.

>  So all nodes are
>really blank; some are identified by a statement like the second N
>Triple.  However, I now think that is probably not be correct [1,2,3,4],

Right, it is not; but...

>and the OWL property, "owl:sameIndividualAs", is not suited for general
>identification.

... I am not sure what you mean by that. OWL's sameIndividualAs 
refers to whatever the nodes denote: it doesn't refer to the nodes 
themselves. So for example

http://www.coginst.uwf.edu/~phayes  owl:sameIndividualAs  phayes@ai.uwf.edu .

is saying (falsely) that I am my mailbox.

Pat

-- 
---------------------------------------------------------------------
IHMC					(850)434 8903 or (650)494 3973   home
40 South Alcaniz St.			(850)202 4416   office
Pensacola              			(850)202 4440   fax
FL 32501           				(850)291 0667    cell
phayes@ai.uwf.edu	          http://www.coginst.uwf.edu/~phayes
s.pam@ai.uwf.edu   for spam
Received on Friday, 6 June 2003 10:09:06 GMT

This archive was generated by hypermail 2.2.0+W3C-0.50 : Monday, 7 December 2009 10:52:46 GMT