Williams, Stuart (HP Labs, Bristol) wrote:
Hello Xiaoshu,
<snip/>
What makes me reverse my course? As I can now understand, the reason is
that when we are speaking at the higher level, there are only a few
words/concepts that we can use. For the Web, there are only three
things that are clearly defined. URI, awww:Representation,
Resource.
According to the SIR model that I have used to define all information
system,
URI is the *Symbol*
awww:Representation the *Information*,
Resource the *Referent*.
Resource, is thus, what exists in the Web. Existence, according to
Quine's definition, is the value of a bounded variable. It is things
that has meaning or significance.
Representation is Information, which, as defined by Dretske, is
objective. And Information must have structure, which, w.r.t. to the
Web, it is the format of awww:Representation.
I really don't think you are very far way from where I, the TAG and probably
most of the web community are - though we (you and I at least) seem make a lot
'noise' about the apparent disagreement.
What seems missing here is a discussion of how the "information" stands in relation to
the "referent". AUI in webarchitecture the intention is that the 'information' conveys
the current state of the 'referent'. With that constraint... if you provide 'information' that
enables me to present an 'image' or a 'narrative' on a screen - it is that 'image' or that
'narrative' that is the referent as opposed to whatever thing or combination of things that are the
subject matter of the depicted in the image or discussed in the narrative.
I have thought about this issue too. I understand your concern. For
instance,, if the light-information emitted from an object makes me to
believe that the object is red. Then, I would prefer that the object in
question is the source of information, i.e., either by emitting or the
light bounced off it.
The most fundamental answer (i.e., I am speaking without another other
terminologies) is that if you want to make sure of the Referent in
question is the source of information, you need more evidence. This is
what we do in science and in social life (such as to dispute rumors).
In terms of the Web, this comes down to the dual nature of the HTTP-URI.
If you treat the HTTP-URI as a URN, I don't think you will have that
concern anymore. Your concern is mostly because the HTTP-URI is also
URL. Hence, when we are talking about resource denoted by an HTTP-URI,
we don't know when we are using it in which sense. So, additional
evidence needed to tell the one sense from the other.
This is why I have proposed the scheme-less URI as the only URN for the
Web. (Thanks for pointing me out its potential conflict with relative
URI. Nevertheless, if TAG really takes this proposal, that can be
easily solved).
Hence, if "//example.com/XiaoshuWang" is used to denote me. The
information returned by "http://example.com/XiaoshuWang"; would not
indicate that its source is from "//example.com/XiaoshuWang". The
"http:" only suggests that it is providing information about
"//example.com/XiaoshuWang". Similarly, if there were another protocol
called *call*, which by some regulation and technology, to connect to my
phone, then you can do "call://example.com/Xiaoshu", i.e., to call me in
real person. If you trust the *call* protocol, then you can remove your
doubt. Otherwise, you will also need more evidence to reinforce your
belief as with the "http" case.
Xiaoshu
Thus, when we talk about the Web, these are all the terminologies that
we have at our disposal. Any other terminologies, such as IR, or Meta-,
Description etc. needs a concrete definition and could be used either a
small sub-system of the Web (hence making it unsuitable as a generic
design pattern for the Web) or someone needs to come up with a model
that making these concepts an essential component of the Web.
I wish this clearly outlined my position (so I won't be accused of
refusing to understand other's position). Hopefully, it can also give
us a reasonable guideline for the subsequent debate if any.
Xiaoshu
Stuart
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