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Re: Uniform access to descriptions

From: Pat Hayes <phayes@ihmc.us>
Date: Wed, 9 Apr 2008 11:41:47 -0500
Message-Id: <p06230902c4229ed8ba8b@[10.100.0.20]>
To: wangxiao@musc.edu
Cc: Dan Brickley <danbri@danbri.org>, "Williams, Stuart (HP Labs, Bristol)" <skw@hp.com>, Jonathan Rees <jar@creativecommons.org>, "www-tag@w3.org WG" <www-tag@w3.org>, Phil Archer <parcher@icra.org>
At 3:50 PM +0100 4/9/08, Xiaoshu Wang wrote:
>Pat Hayes wrote:
>>At 2:51 PM +0100 4/9/08, Xiaoshu Wang wrote:
>>>Pat Hayes wrote:
>>>>At 8:58 AM +0100 4/9/08, Dan Brickley wrote:
>>>>>Hi Pat,
>>>>>
>>>>>Pat Hayes wrote:
>>>>>>At 7:52 PM +0100 4/8/08, Xiaoshu Wang wrote:
>>>>>>>Pat Hayes wrote:
>>>>>>>>At 5:54 PM +0100 4/8/08, Xiaoshu Wang wrote:
>>>>>>>>>Stuart,
>>>>>>>>>>Wrt to that resolution... a 303 response means *nothing*... 
>>>>>>>>>>if you happen to follow the redirection and find something 
>>>>>>>>>>useful about the thing you originally inquired of, that you 
>>>>>>>>>>trust and are prepared to stick in your reasoning engine, 
>>>>>>>>>>then you win - if not, of itself, the redirection has told 
>>>>>>>>>>you nothing/means nothing.
>>>>>>>>>>
>>>>>>>>>>200 tells you that the response convey as representation of 
>>>>>>>>>>the (state of?) referenced thing.
>>>>>>>>>>
>>>>>>>>>If this is what TAG accepts, i..e, 200=*representation of* 
>>>>>>>>>as oppose to "resource of".  I have no problem and would be 
>>>>>>>>>happy with it.  My perception is that TAG is recommending 
>>>>>>>>>either explicitly or implicitly the latter viewpoint.
>>>>>>>>
>>>>>>>>Gentlemen, please both of you speak very slowly and carefully 
>>>>>>>>at this point, as a precise understanding here is critical.
>>>>>>>>
>>>>>>>>Stuart, did you mean that the response conveys/ a/ 
>>>>>>>>representation/ in the webarch sense/ of the referenced 
>>>>>>>>thing? It would be helpful if every time the word 'represent' 
>>>>>>>>and its cognates are used in this very special sense, such 
>>>>>>>>usage were explicitly flagged, as it can very quickly lead to 
>>>>>>>>incomprehension when understood more broadly (as it is almost 
>>>>>>>>everywhere else in the English-speaking world.)
>>>>>>>>(Xiaoshu: from which it follows that in this case, the 
>>>>>>>>referenced thing in question must be something that/ has/ a 
>>>>>>>>webarch-representation; so, in this case, it/ cannot/ be some 
>>>>>>>>other kind of thing that cannot, by virtue of its very 
>>>>>>>>nature, have such a (webarch-)representation; so, to refer to 
>>>>>>>>such things - such, as we now might say,/ non-information 
>>>>>>>>resource things/ - requires something other than a 200 
>>>>>>>>response. Thus goes the http-range-14 logic, as I understand 
>>>>>>>>it. Note that in order to follow this, all we need to know is 
>>>>>>>>that there are things which (a) cannot have a representation 
>>>>>>>>in the webarch sense but (b) that we might wish to refer to 
>>>>>>>>with a URI.
>>>>>(aside: perhaps 'http(s) URI' was meant here, rather than just 'URI'?)
>>>>>>>>Their exact nature need not be specified, but I believe that 
>>>>>>>>the language of 'information resource' boils down to  an 
>>>>>>>>attempt to characterize this category of [/things that cannot 
>>>>>>>>be webarch-represented by a byte stream/]. And, centrally 
>>>>>>>>important, not having a representation in the webarch sense 
>>>>>>>>does/ not/ mean not having any kind of representation, being 
>>>>>>>>unrepresentable, or not being describable. The webarch sense 
>>>>>>>>of 'representation' is very specialized and narrow.)
>>>>>>>Pat, as I have detailed argued here 
>>>>>>>http://dfdf.inesc-id.pt/tr/web-arch.  There can have only one 
>>>>>>>consistent interpretation, that is: there is no so-called 
>>>>>>>"information resource".
>>>>>>
>>>>>>The key issue is not what is an information resource, but what 
>>>>>>isn't. So, in your document you ask, what makes the claim "A 
>>>>>>person is not an information resource" true? And it seems to me 
>>>>>>that this at least has a clear answer: because a person is/ 
>>>>>>not/ something whose essential characteristics can be conveyed 
>>>>>>in a message.
>>>>>I don't know what 'essential characteristics' are. Really. What 
>>>>>are the (erm...) characteristics of the 'essential 
>>>>>characteristics' of some [named type of] thing? Who gets to 
>>>>>decide?
>>>>
>>>>I'm reading 'essential characteristics' as meaning, roughly, what 
>>>>in OntoClean are called 'rigid properties' and what are often 
>>>>called 'essential properties', meaning properties or aspects of a 
>>>>thing which it has necessarily, i.e. which if it didn't have 
>>>>those it would cease to be what it is. Among my essential 
>>>>characteristics, for example, is my being human; or if you 
>>>>prefer, mammalian. And although we have the word "human" in 
>>>>English, its impossible to convey the/ property of being human/ 
>>>>in a message.
>>>But, what is the rigid property of being a document?
>>
>>Exactly that: i.e. being a document. I can recognize documents when 
>>I see them.
>Does it say 200 or 303 or IR?

No.

>>>How to convey "the property of being document"?
>>
>>You send the text of the document in such a way that it can be 
>>displayed. Then I look at it and I/ see/ that it is a document. 
>>This assumes of course that digitally encoded documents count as 
>>documents, which they now do. 50 years ago, they probably would not 
>>have, but cultural attitudes change towards such things.
>I will do a simple word substitution to use your argument for human.
>
>You send the text (image) of (the document => human) in such a way 
>that it can be displayed. Then I look at it and I/ see/ that it is a 
>(document =>human).

No. I look at an image of a human and I see that it is an image. 
Perhaps an image of a human, but still an image. (If an actual human 
were to arrive inside my computer, it would make a huge mess and 
probably short out my power supply.) But when I look at a document 
(token), I really do see (a token of) the actual document.

>This assumes of course that digitally encoded (documents=humans) 
>count as (documents=>humans), which they now do.

Again, digitally encoded humans don't count as humans, because they 
don't exist (and likely never will).

>50 years ago, they probably would not have, but cultural attitudes 
>change towards such things.
>>>If you answer is "document is what is digitizable".  Then, you 
>>>have a subclass of document - digital document but not the 
>>>document itself.
>>
>>Again, a cultural shift of perspective. In current usage, it seems 
>>that 'paper document' is a subclass of 'document', the latter 
>>including all kinds of digital entities which never make it to 
>>paper.
>But, then a URI never identifies the "document", yes?  How do you 
>know the nature behind "http://dfdf.inesc-id.pt/tr/web-arch", is it 
>a document or, an electronic one, or a paper document, which I do 
>have one, or a plastic one, which I don't but could nevertheless 
>make one if I want to.  Does its form matter to you?

All that matters (to me, and I may not be exactly aligned with the 
TAG here) is the distinction between things that can send, or be, 
messages over wires (I don't really care about making this 
sub-distinction exact) and things that cannot.

>>>  Then, there is a subclass of digital Human, which is digitizable too.
>>
>>digital human?? Ive never met one yet.
>Ask Newton about digitized document, he will give you the same answer.

So what is your point? That one day there might be digitized humans, 
so we have to allow for them now? I don't accept this as a reasonable 
position to adopt.

>>Um.. don't confuse a digital object with a digital representation 
>>of an object. Many non-digital things can have digital 
>>representations (though not webarch:representations).
>Isn't it you who intend to confuse but not me?

Well, I don't intend to confuse :-)

>  I tried to tell you that "http://dfdf.inesc-id.pt/tr/web-arch" 
>denotes a digital object, but you can get a digital representation 
>of it from the web.

Yes, I agree with both of these.

>  But it is you who insist to say that 
>"http://dfdf.inesc-id.pt/tr/web-arch" is a digital representation, 
>but not a digital object, right?

No. It is digital, and you can get digital representations of it. You 
can get digital representations of me, in a broad sense of 
'representation' (not webarch:representations though), but Im not 
digital, myself. So just being able to get digital representations of 
something doesn't distinguish it in any special way. Being able to 
get digital webarch:representations of it, however, which is what 
Stuart was talking about, does require it to be digital.

Pat

>>>  The purpose of the web is not about how to digitize resource but 
>>>to communicate resource through its digitized form.
>>
>>Do you mean, communicate the/ actual/ resource, or communicate/ 
>>something about/ a resource?
>My earlier sentence is communicate our viewpoint of a resource 
>(through its digital representation).
>
>Xiaoshu


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Received on Wednesday, 9 April 2008 16:42:31 GMT

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