W3C home > Mailing lists > Public > uri@w3.org > July 2003

Re: Proposal: new top level domain '.urn' alleviates all need for urn: URIs

From: Michael Mealling <michael@neonym.net>
Date: 09 Jul 2003 14:41:27 -0400
To: Sandro Hawke <sandro@w3.org>
Cc: Patrick.Stickler@nokia.com, hardie@qualcomm.com, uri@w3.org
Message-Id: <1057776087.27314.101.camel@blackdell.neonym.net>

On Wed, 2003-07-09 at 14:35, Sandro Hawke wrote:
> > > I'm using the word "same" in the normal dictionary sense of being
> > > truly and completely indistinguishable.  If I tell you <Jim>
> > > owl:sameAs <James>, then you know I'm using the terms "<Jim>" and
> > > "<James>" as synonyms, as two names for the same thing.
> > 
> > Absolutely correct! _You_ have told me that "Jim" and "James" are
> > synonymous. But RFC 2396 provides no method for making such statements.
> I can put aside the OWL terminology entirely.
> You seem to be saying that 
>     http://www.w3.org/
> and
>     http://WWW.w3.org/
> could not possibly ever both identify the same resource.  You seem to
> be saying that if two URIs are textually different, they cannot
> possibly identify the same thing.

It depends on where in Tim's taxonomy of normalization you are. Since
you deal with the 'http' scheme a lot I assume you can normalize that
down to something that allows you to compare them via string
equivalence. If you were in the LDAP world and had no need to know about
the 'http' scheme then you wouldn't be able to do that scheme specific
normalization step that would allow you to do that comparison.

I.e. if I knew nothing about the http scheme then yes, they are
different URIs and thus different Resources. Remember, I live in a world
that doesn't understand the 'http' scheme. No 'representations',
'redirects', or any other 'http' specific semantics. 

> If you are saying that, you are making the "unique names assumption"
> (UNA) for URIs, and living in a world in which RDF and OWL cannot work
> as currently specified.

I never said my very simplistic definition of 'sameness' is the only one
that's allowed. Its simply the only one that's universal. OWL and RDF
can make statements about degrees of sameness between two URIs all day
long. They just have to be explicit about doing so....

Received on Wednesday, 9 July 2003 14:42:49 UTC

This archive was generated by hypermail 2.3.1 : Tuesday, 6 January 2015 21:25:06 UTC