W3C home > Mailing lists > Public > w3c-rdfcore-wg@w3.org > July 2001

Re: Literals as Resources (was RE: draft partitioning of the issues)

From: Aaron Swartz <me@aaronsw.com>
Date: Thu, 5 Jul 2001 00:56:09 -0500
Cc: "rdf core" <w3c-rdfcore-wg@w3.org>
To: "Ron Daniel" <rdaniel@interwoven.com>
Message-Id: <20010705055610.PSOJ22728.femail19.sdc1.sfba.home.com@localhost>
On Friday, June 29, 2001, at 03:34  AM, Ron Daniel wrote:

>> As I have stated and will repeat, I have never seen the M&S
>> state that Literals and Resources are disjoint.
>
> I have already cited section 2.1 of the spec, which says:
>
>     The object of a statement (i.e., the property value) can
>     be another resource or it can be a literal; [...]
>
> This seems pretty clear. But if you disagree, is there a
> particular standard of proof for supporting evidence you
> would have to see before acknowledging that the 1.0 M&S
> considers the two to be distinct?

M&S does not operate in a vacuum. I assume that we also hope to 
align M&S with the other web architecture specs. So the standard 
of proof I would like is an explanation of why M&S's definition 
of Literal does not fit the URI RFC's definition of Resource.

> How about:
>
> 1) A member of the original working groups (me) has stated
>    that their recollection was that the two were considered
>    distinct. (That is a pretty strong recollection BTW).

The Working Group has made a number of mistakes. It was my 
understanding that we were here to fix them.

> 2) The spec has many examples of simple quoted strings as
>    values, or URI references as values. But it has no examples
>    of data URLs or any examples showing how a literal is
>    mapped into a Resource or vice versa.
>
> 3) All RDF parsers and APIs I am familiar with treat literals
>    as distinct from resources, which is a pretty solid
>    verdict from implementation experience.
>
> 4) Art Barstow asked the WG if anyone was familiar with
>    implementations that did not treat them as distinct.
>    Nobody has replied in the affirmative, although Jan
>    Grant said that he could change his code to make it so.
>    But the point is that this would be a change.

Literals can be a subset of Resources and the above can remain true.

> So let's turn this around. What evidence can you provide
> showing that the 1.0 M&S spec considers them to be the same?
> Since you are the one requesting this, the onus is on you
> to show that it is only a clarification, or if it is a change,
> that there is enough implementation experience showing it is
> a needed change.

The evidence is clear in the definitions of Resources and 
Literals in the many Web architecture specs. I simply don't 
understand how a Literal is not a resource -- something with 
identity.

> To keep the length of this message tolerable, I will
> forego the topic of whether this is really a simplicication.

I'd also be interested in hearing your position on why this.

--
       "Aaron Swartz"      |              The Semantic Web
  <mailto:me@aaronsw.com>  |  <http://logicerror.com/semanticWeb-long>
<http://www.aaronsw.com/> |        i'm working to make it happen
Received on Thursday, 5 July 2001 01:56:12 EDT

This archive was generated by hypermail pre-2.1.9 : Wednesday, 3 September 2003 09:38:06 EDT