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

Re: Uniform access to descriptions

From: Alan Ruttenberg <alanruttenberg@gmail.com>
Date: Sun, 13 Apr 2008 23:57:21 -0400
Message-Id: <498700C8-B6C1-4690-80D5-CAD20405FD4E@gmail.com>
Cc: "Eric J. Bowman" <eric@bisonsystems.net>, Pat Hayes <phayes@ihmc.us>, Michaeljohn Clement <mj@mjclement.com>, "www-tag@w3.org WG" <www-tag@w3.org>, noah_mendelsohn@us.ibm.com, Jonathan Rees <jar@creativecommons.org>, Phil Archer <parcher@icra.org>, "Williams, Stuart (HP Labs, Bristol)" <skw@hp.com>
To: wangxiao@musc.edu

On Apr 13, 2008, at 8:29 PM, Xiaoshu Wang wrote:
> Alan Ruttenberg wrote:
>> On Apr 13, 2008, at 6:53 PM, Xiaoshu Wang wrote:
>>
>>>  I failed to follow what is the difference between / 
>>> representation/ vs. /description/
>>
>> You can make a distinction between them like this:
>>
>> Think about describing. When you describe something to someone you  
>> say some things - you make some assertions about the thing.  
>> Suppose you ask someone to describe what Alan looks like. You  
>> could say "he has (some) brown hair". "he has a beard". Even if  
>> the person was talented and able to draw Alan, they would say,  
>> when describing Alan: "He looks like this" (pointing at the picture).
>> On the other hand, think of the goal of representation as re- 
>> presentation. A representation of Alan might be a drawing or a  
>> picture, i.e. it may not necessarily be a set of assertions. On  
>> the other hand, some descriptions can be used as representations  
>> (have to think about whether *all* descriptions are  
>> representations). In any case, not all representations are  
>> descriptions, since not all representations are in the form of  
>> assertions.
>

> I can understand your viewpoint.  But you know I am a very simple  
> minded person (:-)).  If I cannot find a clear-cut definition, I  
> simply won't make it.  Here is my viewpoint, which I don't think it  
> is important, but just want to illustrate my understanding.
>
> First, I simply take machine agents as a different kind of human  
> beings.  They speak a different language than the rest of native  
> languages.  When I say "x is read" in English is no different from  
> "x color red" in RDF. It is simply the latter has much simpler  
> grammar and its user is less intelligent than humans.
I'm with you so far.
> RDF itself indeed doesn't has much logic in there.  RDFS/OWL  
> gradually provided it for somewhat more intelligent agent.  But in  
> between there are many other specialized representation/agents who  
> can handle different kind of representations.  An image is simply a  
> pictorial representation/description of a resource, so does an  
> audio file or even a binary data.

> Our object in the web is communication through sharing resources.
Well, according to the architecture the web is communication through  
sharing representations ;-)

> Hence, all /representation/descriptions/ are doing one thing - to  
> facilitate to understand by all means.
Actually, there are a lots of things they can do. Perhaps this  
affects your thinking or not. For example, with a
> I just want to say architecturally they are not that much different  
> from each other.  Of course, if useful, we can certainly make  
> certain distinctions.  I have rarely use the word /metadata/ is  
> because of its ambiguity.
It's easy to use wrongly.
> But we should make - again - syntactic definition.  We can define  
> that all data expressed in RDF is /description/, etc.  I don't mind  
> such kind of definition.   It is just like when we design database,  
> we can all the schema the metadata because it is syntactic and  
> clear so it is practical.

I think we could give RDF a special status in Conneg, but I don't  
think I'd go about that by trying to erase the distinction between  
description and representation. Instead, since RDF is flexible  
enough, clarify how RDF can have, in addition to the representation  
task it inherits by being one of a member of the set of  
representations of a resource, it can add, in an unambiguous way,  
additional description.

The thing about the database schema that differs from here is that  
RDF can do both schema and data at the same time.

But you probably remember my feeling about content negotiation. For  
browsing the web it is great. For being clear in SW terms it is awful  
because it gives several different things the same name.

The reason I link LINK header is that it is unambiguously out of band  
from the main communication channel. No matter what happens in the  
awww:representations I know I can add some assertions about the  
resource.

> Not trying to open another /debate/, which I sincerely wish not.  I  
> just want to learn our lesson from  the IR and httpRange-14, which  
> after 6 years, are still continue bothering people (no longer  
> bothering me but, I guess, still many others).
>
> Regards,
>
> Xiaoshu
>
Received on Monday, 14 April 2008 03:57:58 GMT

This archive was generated by hypermail 2.2.0+W3C-0.50 : Thursday, 26 April 2012 12:47:56 GMT