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   Re: [xml-dev] URIs harmful

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Joshua Allen wrote:

> This is similar to the facility in RDF.  If I use as subject:
> http://www.w3.org qualityIs good
> I mean the web page
> But if I use something like
> http://www.w3.org ownerIs _:anon1
> _:anon1 qualityIs good
> I am talking about the W3C
> (the plain English for this is "The owner of http://www.w3.org has good
> quality")

Here I think we come to the nub of the issue.  http://www.w3.org is a 
URI and identifies a resource.  As programmers, there are a couple of 
interesting defined operations: comparing and dereferencing.  The latter 
yields a representation of the resource.

There is no way in the existing architecture of the Web to find out what 
the resource *is*.  There is no way to tell whether you're talking about 
a time-varying bag of HTML bits, or the organization that xml-dev exists 
to bash.  In fact, the Web architecture has no way to talk about (to 
quote BillC) what the meaning of "is" is.

Thus, claiming that your first assertion above is talking about the web 
page is simply without basis in the Web architecture.  The assertion is 
about the resource identified by the URI and (thank heavens) does not 
depend on what the resource is, for any given meaning of "is".

If the working of RDF depends on an assumption that a resource *is* a 
bag of bits, then it's simply broken.

Fortunately, I think the example above is *exactly* why we need RDF. 
There is absolutely zero chance that you and I are going to agree on the 
meaning of meaning, but with RDF I can, for example, build my own 
taxonomy of everything in the world and issue statements like

   http://www.w3.org TimsProperties:Is TimsTaxonomy:VendorConsortium

and build a set of useful inferences from there.  Alternately, I could 

   http://www.w3.org TimsProperties:Is TimsTaxonomy:HypertextDocument

and build on that.  Not only am I saying things about meaning, I'm doing 
so in a way that loads smoothly into databases and supports all sorts of 
useful automatic processing.

> This is why it is so critical that people not be encouraged to say that
> http://www.w3.org IS the W3C.  Because first, you already have a way to
> indirectly identify the W3C, by saying "the owner of http://www.w3.org";.
> And if you start saying that http://www.w3.org IS the W3C, things that
> are perfectly reasonable and logical before such as "the owner of
> http://www.w3.org"; become muddled and suspicious.

I think there is no evidence to support the paragraph above.  If it 
meets my needs to use that URI to denote an organization, and and I have 
RDF properties whose domain is "organizations", why can't I go ahead and 
do this?  The domain of *your* "ownerIs" property may be web pages, and 
thus your assertion is logically inconsistent with my statements which 
treat the URI as representing the organization.  What is the problem 
with this?  Surely nobody imagines that the universe of RDF properties 
are all mutually consistent?

In fact, I suspect that with a little study, you could build some RDF 
properties that link from your assertions to mine, working around the 
inconsistency.  Paraphrasing into English "if w3.org has an owner (in 
Joshua's vocabulary), and if w3.org is a vendor consortium (in Tim's 
vocabulary), then we can conclude that Joshua's anonymous owner resource 
is a Vendor Consortium".

But if you try to base anything on claims concerning what a resource 
*is*, you're off on the wrong foot.

Hmm... this discussion should be happening on rdf-dev or www-tag, 
probably the latter. -Tim


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