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Re: comments on Web Architecture First Edition

From: Pat Hayes <phayes@ihmc.us>
Date: Wed, 5 May 2004 15:00:35 -0500
Message-Id: <p06001f0bbcbee3821ba6@[10.0.100.76]>
To: Dan Connolly <connolly@w3.org>
Cc: public-webarch-comments@w3.org, w3c-rdfcore-wg@w3.org
>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 Wednesday, 5 May 2004 16:00:47 EDT

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