W3C home > Mailing lists > Public > www-rdf-rules@w3.org > July 2005

Re: Web Rule Language - WRL vs SWRL

From: Ian Horrocks <horrocks@cs.man.ac.uk>
Date: Fri, 1 Jul 2005 22:25:58 +0100
Message-Id: <7ce165e06c7c49479d2eb212ea8ba14d@cs.man.ac.uk>
Cc: www-rdf-rules@w3.org
To: Michael Kifer <kifer@cs.sunysb.edu>

On 1 Jul 2005, at 03:10, Michael Kifer wrote:

>
>
> Ian Horrocks wrote:
>>
> [snip]
>
> I deleted most of the discussion, because it was already addressed in
> another message or became pointless.
>
>> On 30 Jun 2005, at 04:11, Michael Kifer wrote:
>>
>>>
>>> *Modulo the blank nodes. The post-facto RDF semantics treats blank
>>> nodes as
>>>  head-existential, which is outside of LP. But there is another,
>>> LP-style
>>>  semantics for blank nodes.
>>
>> We seem to be back to discussing RDF with a different semantics than
>> the one it *actually* has. If we assume that it would be possible to
>> give RDF syntax an alternative LP style semantics, then we would have
>> two completely separate language towers, one based on RDF and the 
>> other
>> based on RDF-LP. This was *exactly* the point we were making in our
>> paper.
>
> First, it is not too late to fix the mistakes in RDF. As far as I 
> know, the
> implementations of N3 don't respect the existential semantics of blank
> nodes. And you kept saying in this thread that N3 is an RDF language.

Interesting. It seems that OWL and RDF are either:

a) useless, because no one understands them and/or can use them 
correctly, or
b) broken, and need to be "fixed".

It is good that your position on this is now clear.


>
> Second, you never hesitate to place OWL as a whole (incl DL) on
> top of RDFS, while you know that this is not the case.

I agree that the situation w.r.t. OWL-Lite/DL is not as straightforward 
as we would like it to be, but there is a large measure of semantic 
interoperability between these languages and RDF, as can be seen from 
the running example, further details of which are given in my reply to 
Sandro [1].

Ian

[1] http://lists.w3.org/Archives/Public/www-rdf-rules/2005Jul/0012.html

>
>
> 	--michael
>
Received on Friday, 1 July 2005 21:26:04 GMT

This archive was generated by hypermail 2.2.0+W3C-0.50 : Monday, 7 December 2009 10:53:12 GMT