W3C home > Mailing lists > Public > www-tag@w3.org > April 2008

Re: Announcement: "Cool URIs for the Semantic Web" - W3C SWEO IG Note

From: Pat Hayes <phayes@ihmc.us>
Date: Wed, 9 Apr 2008 00:12:21 -0500
Message-Id: <p06230904c41fdea150c2@[192.168.1.2]>
To: Leo Sauermann <leo.sauermann@dfki.de>
Cc: www-tag@w3.org, SWIG <semantic-web@w3.org>
Nice document. A few quibbles:

-----------

"Given such a URI, how can we find out what it identifies? We need 
some way to answer this question, because otherwise it will be hard 
to achieve interoperability between independent information systems. "

I know you probably don't want to get involved with philosophical 
issues, but this sentence is so wrong as to be misleading. We CANNOT 
POSSIBLY find out what any name identifies, other than by being 
explicitly handed the thing or being pointed to it (as in the 
pre-semantic Web). The best we can POSSIBLY do is to have a detailed 
enough description of the thing for our purposes; but no description 
can completely identify a single thing. So your second sentence above 
is particularly misleading: it suggests that the Web will not work 
unless we all do something impossible before breakfast.

Moreover, getting involved with this highly debatable issue isn't 
needed, to motivate the subsequent content of the note. The point is 
not that we need to be able to discover what exactly it is that 
non-document URIs denote. The central point is only that, pretty much 
by definition, they denote something that isn't a document, which is 
why we need to distinguish the URI for the thing from a URI for any 
document/"information resource" which describes the thing. You can 
avoid the philosophical/semantic tar-pit of the nature of reference 
and how it can be determined, by sticking to this basic point in your 
introduction.

------------

"When using 303 URIs for an ontology, like FOAF, network delay can 
reduce a client's performance considerable."

This sentence is not grammatical English. Rewrite to:

When using 303 URIs for an ontology, like FOAF, network delay can 
considerably reduce a client's performance.

or:

When using 303 URIs for an ontology, like FOAF, network delay can 
reduce a client's performance to a considerable degree.

-----------

Section 4.4 , first paragraph, has a misleading rhetorical structure. 
It says that hash URIs can be used so that a family of URIs share a 
non-hash part, then observes that this approach has a downside, then 
presents 303 as an alternative which avoids the problem. But of 
course one can avoid this problem while still using hash URIs, simply 
by NOT having a family of URIs which share the non-hash part. You 
present this idea later in the section, but describe it, 
misleadingly, as 'combining 303 and hash'. As far as I can see, 
http://www.example.com/bob#this has nothing to do with 303: it is a 
straightforward use of a hash URI.

It is also a beautifully simple and uniform way to handle the whole 
issue, by the way, avoiding all this 303-redirect craziness at a 
single elegant stroke. You ought to make more of it.

------------

Best wishes

Pat Hayes
-- 
---------------------------------------------------------------------
IHMC		(850)434 8903 or (650)494 3973   home
40 South Alcaniz St.	(850)202 4416   office
Pensacola			(850)202 4440   fax
FL 32502			(850)291 0667    cell
http://www.ihmc.us/users/phayes      phayesAT-SIGNihmc.us
http://www.flickr.com/pathayes/collections
Received on Wednesday, 9 April 2008 05:13:03 GMT

This archive was generated by hypermail 2.2.0+W3C-0.50 : Thursday, 26 April 2012 12:47:55 GMT