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RE: comments on Web Architecture First Edition

From: Williams, Stuart <skw@hp.com>
Date: Thu, 6 May 2004 12:36:26 +0100
Message-ID: <E864E95CB35C1C46B72FEA0626A2E808031A8F8B@0-mail-br1.hpl.hp.com>
To: Pat Hayes <phayes@ihmc.us>, Dan Connolly <connolly@w3.org>
Cc: public-webarch-comments@w3.org, w3c-rdfcore-wg@w3.org

Dan, Pat,
 
Speaking personnally I have a lot of sympathies with the problems that Pat
has found with our document and the frustration it engenders. The two
senses, which he dubs (C) and (D), of our use of the terms "(semantic,
represent, identify, refer, about, meaning, resource) "  are recognisably
present (IMO) and I feel that Pat has gone a long way toward diagnosing and
detailing the problem. I for one have found his comments interesting and
helpful. I actually find it reassuring that Pat has found a reading under
which "almost the entire document makes perfect sense" although I'm not sure
which reading he regards Dan/Roy as rejecting - I too need to re-read much
of this to restore context. I would also want to aim to produce a document
that at the end of this process Pat actually finds useful, rather than
worthy of an F "in a high-school English class". I'd also want to enlist his
help in that venture.
 
To focus on a bit of the actual commentary below. Pat, you pick on the
following sentence several times.
 
"The World Wide Web is a network-spanning information space of resources
interconnected by links"
 
I'll admit that I think it could be clearer. You repeatedly question whether
various conceptual and real-world articfacts (sometimes distant real-world
artifacts) are actually "interconnected by links":
 
> I take it then that a resource is something that can be connected by a
> link to another resource. I presume also that "link" here means more
> than simply a reference to something,  but connotes an actual connection 
> of some kind (eg along which information can be transmitted.)
 
I read the work "link" in that sentence simply as a reference to something
and the sense of "connectedness" to be the existence of such references. I
certainly don't take it to mean the existence of some 'physical' connection
or medium "along which information can be transmitted". The sense of
'interconnectedness' by 'links' feels to me like (directed) arc's in a graph
migh the said to connect the nodes in the graph.
 
I don't know whether that give more or less comfort, but that is how this
TAG member reads the phrase "resources interconnected by links". [And I'd be
happy with entities (or thing) instead of resources, but that's confusing
for XML people for whom the word "entity" has yet another meaning, and I can
live with resources because the us an R in URL, URI and URN which does seem
to be the local vernacular].
 
I think that some of the 'polemic' in your response follows a reading of
interconnection and links as "an actual connection" and the assertion you
then make seem bound to that reading. I guess the sense of physical links
(rather than mere references) is encouraged by the "network-spanning"
adjective (? F for English :-))  early in the sentence.
 
I agree that there is a difference between these two senses. The notion of a
'link' on the web has long been associated with the making of such
references, so I don't think it's use in this context is as alien as you
appear to portray it. I'd be happy to use other words than 'connected' like
'related' or 'associated'. I'm also (I think) comfortable with the notion
that some resources are incapable of making such 'references'  - but I
suspect I risk zig-zagging across the (C)/(D) line.
 
I've had some thoughts about how we might more globally address your concern
which I'll write up separately and see how they fly. They are in similar
vein to parts (but not all) of TimBLs response on this thread [1].


Best regards
 
Stuart
--
[1] http://www.w3.org/mid/7709C979-842C-11D8-A0E3-000A9580D8C0@w3.org


________________________________

	From: public-webarch-comments-request@w3.org
[mailto:public-webarch-comments-request@w3.org] On Behalf Of Pat Hayes
	Sent: 5 May 2004 21:01
	To: Dan Connolly
	Cc: public-webarch-comments@w3.org; w3c-rdfcore-wg@w3.org
	Subject: Re: comments on Web Architecture First Edition
	
	

		On Wed, 2004-03-17 at 16:38, Pat Hayes wrote:


	Sorry about long delay in responding, your message apparently got
lost somewhere.


		> The following are some personal comments on
		> http://www.w3.org/TR/2003/WD-webarch-20031209/
		> Sorry they're late.
		>
		> ------
		>
		> 1. General comment about vocabulary
		>
		> The vocabulary used throughout this document can be
understood in two
		> rather different ways,
		
		yes...
		
		>  which conflict with one another.
		
		Do they? Are you quite sure?


	They certainly seem to. That is, there is wording throughout the
document which makes sense under one reading but not under the other, both
ways round. I have been drawn to this 'two-senses' conclusion by a series of
extended and in some cases mind-bending attempts to make sense of the
document (and previous documents on the same general topic.) I have not come
to this conclusion lightly, or imposed it from a preconception. In fact, I
started with the preconception that resource=entity, as summarized in the
RDF semantics, and as you once explained to me, but felt obliged to reject
that or at least qualify it, given what is said in the bulk of the document.


		I have heard this claimed many times,
		and I have never seen a convincing argument. I am looking at
		your comments for just the 2nd time; the first time was just
		a quick skim.
		
		Your claim sounds very reminiscent of
		  "The Myth of Names and Addresses"

		  http://www.w3.org/DesignIssues/NameMyth.html
		I cite that not as an argument from the TAG, but as
		evidence that this line of argument is perennially raised,
		but not persuasively.


	It SOUNDS reminiscent, but it is not the same point. I had not
previously read this old thing of Tim's, but I think I see how some of the
confusion may be traced to it. He is talking there about a different matter
entirely, about two senses of identifier:

	"This can lead us easily into imagining that there are two types of
objects: Names, which once attached to an object follow it for its life
wherever it should reside, and "addresses" which change frequently whenever
an object moves or is copied or replicated from one "location" to another."

	The key distinction here is identifying the thing - what Tim calls
"name" -  versus identifying the location - "address"; a difference which is
made vivid when the thing moves to a different address. OK, good point, one
worth making in an architectural context: but not what I am talking about. I
am talking about 'names' (not in Tims sense) which have got NOTHING WHATEVER
TO DO with addresses of any kind, which are entirely removed from any
architectural or computational sense of 'naming' at all, and which are not
'identifiers' in the same sense (because they cannot in general be
"dereferenced" in the sense that Tim is talking about): the kind of names
and naming that were around in human society ever since apes started
grunting to indicate things in the external world, the kind of names that
pre-dated the computer by several dozen millennia. Just FORGET about
computers and networks and architecture and the entire WWWeb for a second,
if you can, and just think of LANGUAGE and REFERENCE. How WORDS refer. That
is what I am trying to talk about. That is what the Sweb semantics is an
idealization of. It has got almost NOTHING directly to do with networks.

	(BTW, there are some actual errors in that old thing of Tim's, FWIW,
and also I think a more basic misunderstanding, in which he assumes a much
too restricted notion of 'place' or 'address' . But maybe he was arguing
against folk who had too restricted a notion, back in 1996.)



		[...]
		> In particular, in sense (C), but not in sense (D), there
is a
		> presumption of a computable or effective process which can
be applied
		> to the identifier to provide access to the entity
identified;
		
		no, I don't believe there is any such presumption in the
webarch
		document.


	Oh, surely this assumption is implicit throughout the document. It
says for example that resources are connected by networks, that they can be
accessed and operations performed on them by network protocols, etc. ; less
directly, the idea that resources have a unique identifier has no rational
basis for anything other than nodes which must be somehow addressed on a
network in order to support transmission protocols.



		[...]
		
		> 2. Hunting down what is meant by "resource".
		[...]
		> The latter (D) interpretation seems to be insisted upon by
the cited
		>
documenthttp://gbiv.com/protocols/uri/rev-2002/rfc2396bis.html
		> which reads:
		> "Resource
		>     Anything that can be named or described can be a
resource.
		> Familiar examples include an electronic document, an
image, a service
		> (e.g., "today's weather report for Los Angeles"), and a
collection of
		> other resources. A resource is not necessarily accessible
via the
		> Internet; e.g., human beings, corporations, and bound
books in a
		> library can also be resources. Likewise, abstract concepts
can be
		> resources, such as the operators and operands of a
mathematical
		> equation or the types of a relationship (e.g., "parent" or
		> "employee"). "
		>
		> Which could be paraphrased as "A resource can be anything,
and
		> everything is a resource".
		
		yes, quite.


	Well, then, it is hard to resist asking the question, why did y'all
feel obliged to (mis)-use a word when there already were perfectly good
words you could have used, such as "entity" or even the plainer "thing" ?
Grice's maxims come into effect at this point in the reader's mind: they
aren't using the ordinary word, so they must intend a special sense...try to
figure out what it is....



		>  I note particularly the phrasing "named or described". (I
also note
		> in passing that the first three "familiar" examples are
hardly typical
		> of entities in general, and that the examples do not
include such
		> things as galaxies, atoms, grains of sand; kinds of
material such as
		> steel or wood; holes, times, locations, intervals; natural
processes
		> such as flows and movements; and many other categories of
entity which
		> have been the subject of formal ontological descriptions.
Are these
		> omissions deliberate?)
		
		I don't think so. As I recall, we just haven't much reason

		to say that wood is a resource.


	Is wood something which can be connected to a network-spanning
information space by a link? Is wood something on which operations can be
performed by means of network protocols? Is wood something that must have a
unique identifying URI? (What would that claim even MEAN? what could it
POSSIBLY mean? )


		> The only example given in the document is disturbingly
vague at
		> precisely this critical point: the resource is the "Oaxaca
Weather
		> Report". But what KIND of thing is that,
		

		It's a resource.


	AAARGH. WHAT DO YOU MEAN BY "RESOURCE" ???

	That answer is VACUOUS since you have not said what you mean by this
damnable word. (It does mean NOT mean resource in the ordinary English sense
of "resource". )

	BTW, to answer in this way deliberately, in case you think
otherwise, is not being philosophically clever, it is just plain bloody
rude.  In effect, by deliberately using this word as the answer when I have
asked you to clarify it, you are telling me to f**k off.  Which at this
point I feel thoroughly inclined to do.


		You seem to feel we need to constrain it more. I don't think
		there's any need to.


	There is a real need to explain what you mean when you use words in
an unusual way. This is not just a quibble: until you SAY what you mean by
this highly non-standard usage, the entire document is literally USELESS.

	I find it hard to believe that we are even having this conversation.
If the TAG group were a bunch of students in a high-school English class
they would get an F immediately for not understanding this basic point.


		>  and how exactly is it related to the URI and the
"representation" of
		> it?  (see later for more on that word)
		
		in that case, it's related by some HTTP protocol messages.
		
		> Several different answers are consistent with what you say
about the
		> example.
		
		And so...?
		
		This seems to be a comment that web architecture is
incompletely
		specified. Yes, it is.


	I was not asking about Web architecture; I was asking about the
MEANING of the WORDS you use to describe it. As I said, almost the entire
document makes perfect sense under the reading that you (and Roy) reject,
the one under which it would indeed be a document describing an
architecture, and did not try to simultaneously be a tract based on an
ill-thought-out (and unpublished) operationalist/pragmatic philosophy of
language which apparently is based on the idea that reference and physical
connection are identical and which assumes that every entity has a unique
True Name. If you really believe this stuff, I think you ought to write it
up and send it to a journal, or at least put it up on a Blog somewhere where
people can comment on it.


		But earlier, you seemed to be claiming that the webarch
document
		is inconsisent.


	It is not written with enough precision to know whether it is
consistent or not. It SEEMS to contain inconsistencies, in the sense that
words and phrases  are used apparently with different and incompatible
meanings in different parts of the document. I have documented this
phenomenon in detail.


		This does not justify that claim.
		
		
		> (a) Do you mean something like an abstraction of a
document, in the
		> sense that "Moby Dick" refers to a resource called a
novel, which is
		> an abstraction of all the printed, spoken etc. tokens of
Moby Dick
		> ever produced (which could be described as
"representations" of it,
		> although "token" is the existing technical term in wide
use here.)
		>
		> (b) Do you mean that the resource here is the actual
weather - the
		> state of the atmosphere - in Oaxacala on the day in
question? So that
		> the HTML 'represents' this in the sense of talking about
it -
		> referring to it, describing it - which is the usual way
that
		> "represent" is used in normal language, formal semantics
and
		> linguistics.
		>
		> (c) Do you mean that the resource here is the thing on the
server that
		> processes the request and which emits the text/html
representation,
		> which is therefore a representation of the state of a
computational
		> entity which is physically attached to the network? That
is, the
		> resource is a computational entity of some kind, or its
state? This
		> would be consistent with the first C sense of 'identify'
and with the
		> description in the first sentence of the abstract
referring to
		> 'resources interconnected by links'.
		>
		> (d) Or do you intend to be systematically ambiguous
between these
		> alternatives, so as to try to apply to them all? I hope
not, because
		> they are not mutually compatible;
		
		There is your claim again, still not justified.


	I am quite willing to justify that claim on quite precise grounds;
in fact, I believe that I already have done so. But there may be no need to,
if y'all can please just use English properly and clarify your intended
meaning.



		>  and if not, it would be extremely helpful if you could
clarify your
		> intended meaning, perhaps by fleshing out the description
of the
		> example with a little more conceptual detail.
		
		Well, the level of detail we have written down so far seems
		to be an improvement over nothing to quite a few people.
		We do intend to elaborate it eventually, but it's not clear
		to me what you need that you haven't got already.


	What you have written is likely to be very useful to people who are
not interested in reference or descriptional semantics. I wish it were
written clearly with that (large) audience in mind. In its present form,
however, the document is not only not helpful, it is positively harmful, to
clarifying the relationship between SW semantics and Web architecture. I
would describe it as corrosive, a major disaster. I think it, or, more
properly, the confusion that it embodies, fails to clarify, and in places
authoritatively reiterates, has been and continues to be a constant source
of misunderstanding, controversy and potentially bad design decisions, and
that until this mess is cleared away we will never get a sensible coherent
account of the foundations of the semantic web.



		> Trying to home in on your intended meaning by searching
the document
		> for uses of "resource" gives the following:
		>

		> [[The World Wide Web is a network-spanning information
space of

		> resources interconnected by links. ]]
		>
		> I take it then that a resource is something that can be
connected by a
		> link to another resource. I presume also that "link" here
means more
		> than simply a reference to something,
		
		why?


	Because that is the usual meaning of the words "link" and
"interconnected" . Reference is not in any sense a connection. I can refer
to things that do not exist, or have ceased to exist, or which might exist
but do not yet exist: I cannot be interconnected to them, by links or
anything else. I can refer to things that I cannot be connected to by virtue
of physical limitations, they being light-years away. I can refer to
abstractions such as numbers or sets, for which it would be logically
incoherent to even suggest that one could be connected in a network sense. I
can refer ambiguously (in fact, I would argue that this is the normal case)
but I cannot be ambiguously connected.  I can refer in one possible
interpretation and refer differently in another, but I do not know how to
get possibly connected in an interpretation. And so on.



		>  but connotes an actual connection of some kind (eg along
which
		> information can be transmitted.)
		
		What's the difference?

	
	
	If you do not understand this then I despair of explaining it to
you. Surely it is OBVIOUS that referring to something is not being connected
to it? Do you think you are linked, in the sense implied by "a
network-spanning information space of resources interconnected by links", to
, say Santa Clause, or Nero, or the great nebula in Andromeda, or to my as
yet unborn great-grand-daughter, or the base of the natural logarithms? Do
you think that simply by mentioning something you are thereby enabled to
perform operations on it, using a kind of network version of Voodoo?



		>  This seems like sense (C), and is not intelligible when
applied in
		> any broader sense.
		
		That's yet another strong claim, without justification.
		
		
		
		I have spent about half an hour reading these comments
without
		finding justification for your claim that our document is
		inconsisent.
		
		I wonder if I could trouble you for a shorter version of
your
		argument?


	No.  Read a book or two about truth and reference. Sorry, but there
just isn't time to do this much re-education: I have a living to earn, and I
don't earn it doing this.

	I've done my best. If you can't follow it by now then I give up. I
will agree to not comment further on the TAG document. In fact I will agree
to not even read the TAG document.

	Maybe someone else can have a try?

	Pat



		[... much elided ...]
		
		--
		Dan Connolly, W3C http://www.w3.org/People/Connolly/
		see you at the WWW2004 in NY 17-22 May?



	-- 
	
	
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Received on Thursday, 6 May 2004 07:37:08 EDT

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