Re: Naming things with hashes (not #, but e.g. md5)

On 11 Apr 2012, at 12:50, Larry Masinter wrote:

> You're not understanding me, and I'm getting tired of trying to explain.
> 
> For example: 
>> Just to be clear, the hr14 resolution has two parts, a 2xx case (a) and a 303 case (b).
> 
> But the hr14 resolution is incoherent because it is a "resolution" to a senseless question, and thus "cases" are meaningless. There is no "2xx case" and a "303 case", any more than there is a "404 not found" case and a "DNS error, server not found" case.  
> 
> If sender A sends 
> 
>    <a href="http://example.org/path">something</a> 
> 
> to recipient B inside a message labeled "text/html", that message expresses the intention that if B displays the result of the message, it will display 'something' with a hyperlink which, when clicked or selected, will attempt to connect to example.org with path /path using the HTTP protocol; other messages in other formats with hyperlinks (PDF, flash, XML, SVG) or with other URI schemes (ftp, data, mailto, etc.) have similar or related meaning.
> 
> I can try to explain by analogy, once more.  If I tell you, "The sky is falling", 
> then what I say is independent of what the OED or the American Heritage
> dictionary say about the words "sky" and "falling". There are references
> you can consult to discover what I might have meant, and our conversation
> is more reliable if I make reference to reliable dictionaries in which you can
> discover definitions of terms I use if those terms are not in (our) common
> use.  But the meaning doesn't inherit from the dictionary or whether you 
> have one or change if your dictionary burns up.

Yes. Having good dictionaries helps us synchronise the meaning of our words
but is not a necessary requirement to having meaning. If it were then meaning
could never have gotten off the ground. David K. Lewis argued this very clearly
in his book "Convention" published in the late 1960ies. He shows game theoretically
how one can have a convention without prior agreement.  Still once dictionaries
exist they make communication much easier, and they allow many more words to be
used. At some point dictionaries can become determining of the meaning of words.
In any case they can reenforce them very strongly. 

> While "follow your nose" may be a "good practice", meaning doesn't
> depend on good practice being followed.

According to Lewis, meaning depends on conventions being followed in enough situations in
such a way that the coordination problem they solve is self re-enforcing.
Driving on the left in the UK is a good idea because everybody else does.
Because everybody else drives on the left in the UK is good reason to 
continue to do so. Sometimes people from the continent forget this when
they come to visit.

Placing a document on the web to define the meaning of a # URI within it
and the follow your nose principle together form very strong re-enforcing 
mechanisms that lead to stable coordination behaviours. 


> The meaning of an instance
> of XML doesn't depend on whether someone has bothered to populate
> the namespace URI's web server with interesting information about
> the URI, and doesn't change when the web site is put up or taken down.

The next part of the philosophy of language we need to take into account
is natural selection. The work of Ruth Garett Millikan here is very useful 
here 
  http://www.philosophy.uconn.edu/department/millikan/index.htm

In order for vocabularies to reproduce they need to be understood and 
lead to coordination synchronisation problems that allows agents that use
them to gain a selective advantage. Not placing documents that describe the
meaning of vocabularies on the web is not going to do a lot for the reproducible
chances of your vocabulary. Hence one can imagine - and there are - situations where
the XML namespace need not be populated for the coordination problem the XML is
attempting to solve to work, but it is clearly going to help communication if it
had. The follow your nose principle, good documentation, and good trustworthy
behaviour of the owners of the vocabularies augments the chances of growth, and
copying: the internet is a huge copying machine and following its architecture is
helpful.

> The reliance on 200 vs 303 vs. 404 vs. "server not found" DNS errors may be
> an artifact of some particular processing systems that actually rely on
> attempting retrieval from URIs used in RDF, but that dependency is an
> artifact of those (poorly designed, IMHO) processing systems, and not
> on the "meaning".

There is an abstract understanding of the meaning of a sentence in terms of 
possible worlds: i.e. the meaning of a sentence is the set of possible worlds
in which it is true. (speech acts, such as promises, orders etc... can be adapted
to this). Since languages have to be learnable they need a grammar that is 
combinatorial, where the meaning of syntactic elements compose with the meaning
of others to form the whole meaning of the sentence. This is 
what grammar provides, and is what leads to the notion that ideas have sex

http://www.ted.com/talks/lang/en/matt_ridley_when_ideas_have_sex.html

(and Millikan does a very good job of showing how this ties into language)
It is also why RDF is so powerful.

In any case there is a relationship between mathematical meaning and natural meaning
and that is a selection function. Languages humans speak are not grammars, symbols and
semantics that are mapped to mathematically pure languages, but to sets of such things.
Ie: languages evolve. At any time we are speaking one of an innumerable number of
sets of possible languages, which scientists make more precise when confronted with
a logical dilemma: i.e. they make selections in the sets of possible languages we speak.

In any case processing systems are what form the way we come to settle on some of the
meanings of things. So they are part of what determines the meaning as a natural selection
function.

> 
> And no, the HTTP working group scope does not cover defining the
> meaning of HTTP URIs outside of a URI as a signifier of invocation of
> the HTTP protocol with a particular host address found within the
> HTTP URI, so saying that your interpretation is "enshrined in HTTPbis"
> is nonsense.

HTTP #uris are given by the returned document. So there is a relation between
the URI in the IETF spec and the document returned.

> 
> 
>> If
>> I ask what an occurrence (in some context) of a name "means", I'm
>> asking what the party who wrote that occurrence intended when they
>> wrote it. 
> 
> I think that's an impoverished model of communication which you insist on sticking with,

It is indeed somewhat simplified, since meaning is determined by coordination problems leading to 
natural selective advantages of the users of the vocabularies (such as software agents for example).
Coordination means that one cannot do meaning alone, unless to coordinate with future time slices
of oneself, in which case though one does have an issue: if the meaning were completely private then
how  would onw know at one point that one was continuing to follow the rules as one had
before? (this is the well known interpretation of Kripke of Wittgenstein's private language argument)

Thinking in terms of coordination and evolution brings the social and physical problems into focus and
helps show how meaning can be objective.


> and which leads to the same senseless conclusions.  I don't think we're going to make progress on clarification
> here if you insist on framing the question in the way you are framing it, and don't think it is worth TAG time to discuss this any more. 
> 
> The sender (A) is communicating with the receiver (B) with a message M that includes a URI U.  U participates in the communication, and the communication of M is effective if A and B share a mutual understanding of M and U's role in it.
> 
> If M is HTML and U appears in a@href, the "meaning" of U in that context is pretty widely understood as establishing some expected behavior in B's software when B clicks on the link, at least for some URI schemes commonly used in URIs within HTML and similar language (there's work ongoing to come to a common agreement when U is an "about:" URI, for example,  on defining expected behavior when U appears within content which is generated by scripts from a different origin, when the result of a retrieval contains content that looks like it matches a different MIME type than the one it was served with, etc.)

yes. you are here following a Dummetian verificationist principle of meaning it seems. The meaning of a sentence according to this
theory is the way one can verify its truth: it is the verification procedure. This theory is very interesting and had a long life in
20th century philosophy. 

But there is another theory of meaning that insists that reality participates in the meaning of the terms. So for
example the colour red is taught by pointing to RED things. Those red things reflect certain light waves that impact
humans in certain ways such that they can use this objective fact about both their neural cognitive set up and the 
the way the world is. You need both to teach the word red. 

Here if I remember correctly Gareth Evans points out that meaning also requires a way the cognitive system can hook
onto the meaning: this would be the minimal procedure which under normal conditions would allow the word's meaning
to be bought. For example the colour red is bought when predicated of objects under normal lighting conditions.
Chrisopher Peacock's latest book "Truly Understood" which I have not yet quite finished goes into this in great and
precise detail. (http://en.wikipedia.org/wiki/Christopher_Peacocke) As I understand Prof Peacock here shows how 
to salvage some of the verificationist intuitions of Dummet without taking it all on board.

From this I think it should appear that placing the definition of a term at a document location even if that
definition does not cover all cases can still give that initial crystallisation seed for creating the
 synchronisation of behaviours that leads to the solving of coordination problems which meaning is about.

> 
> But if M contains a collection of RDF triples and U is used within a triple, there isn't a common widely understood expectation of behavior, at least in terms of processing systems that want use logic processing on the triples retrieved.  This isn't the fault of "U" being badly defined, or the definition of the protocol used if U is accessed as if it were in an a@href, it's a problem in not having a common understanding about M.
> 
> If you continue to insist that "U" has a common "meaning" that is independent of the context use, and at the same time insist that the "meaning" of U within a@href in HTML has nothing to do with the "meaning" of U within an <U> <R> <B> triple in RDF, then you are taking an incoherent position.

There are many dimensions to the context problem. One of them is solved quite well by named graphs. 

> 
> Persistence and equivalence are two URI relationships that depend on context. Within HTML, a URI is "persistent" insofar as it continues to serve as a good target to illustrate the text that is being marked up. So the persistence of <a href="http://www.w3.org/2001/tag">The W3C TAG</a> depends on the web site containing information about the organization, whether or not the organization is disbanded, split into unter-TAG and uber-TAG, or whether MIT forgets to pay the .org renewal for w3.org.

You could say also the Truth of that statement depends on those elements. Or you could say: the possible worlds in which that statement is true depends
on those elements. Possible worlds and modal logics are the logics of context I think: they give you the full variation of context you can work with.

In any case that statements can be true at one point and then become false is part of life. But that allows for the meaning to remain the same.
> 
> Note that, for the most part, within that context http://www.w3.org/2001/tag and HtTp:wWw.W3.orG:80/2001/tag  are "equivalent", insofar as their common behavior. 
> 
> But within <svg xmlns=" http://www.w3.org/2000/svg">...</svg>, the persistence of utility of http://www.w3.org/2000/svg as namespace name doesn't depend on whether the result of a retrieval on the namespace URI is 200, 303, 404, or timeout. And the URI is *not* equivalent to HtTp:wWw.W3.orG:80/2000/svg. 


That is because xmlns is a syntactical element of the purele syntactically defined format XML. You could easily provide semantics in which those mappings were
then considered to be equivalent. I think XML is great because it distinguishes so clearly between syntax of semantics. The pitty is that it then led those
who built it to think they did not need semantics.

> 
> I'm very frustrated with this conversation because I think you are spinning in circles, asking nonsensical questions. I've tried time and time again to provide a basis for discussion that I think is rational, but the conversation keeps on slipping back into what I think is nonsense.
> 
> The reason why this matters and I keep on trying is that I don't think we can have a sensible architectural discussion about privacy, security, CORS, cross-site-scripting, local storage, publishing and linking, and many of the other topics we should be resolving, if you start with a model of communication using URIs that is decontextualized from the message, the actors involved, the time sequence of events and the roles of the players involved in communication.
> 
> I don't think we can begin to discuss those issues meaningfully using the current AWWW model -- it was a nice try, and maybe a reasonable approximation for some purposes, but it's not good enough to help with most of what we're faced with.
> 
> We need to talk about the impact of broken certificate infrastructure, attacks on DNS, the effect of take-down notices and legislatively mandated redirection from acts like SOPA and PIPA, and an model which insists that a URI has an "owner" who is responsible for saying what it's "meaning" is, that model doesn't let us talk about how the web really works.  The fact that AWWW doesn't seem to work resolving some of the more obscure edge cases around linked data and metadata ... it's just more evidence to me that we need to move on.

Really we need a philosophy community group that would help map out the philosophical issues that are hidden
in these debates. I have done a quick job of giving some perspective of what professional philosophers in the 
analytic tradition have been up to in the past century. 

I also covered some of this in my talk "Philosophy of the Social Web" on http://bblfish.net/ 

But there is a lot of interesting work to do here. Btw. At www2012 there will be a philosophy track.
http://web-and-philosophy.org/philoweb-2012-www-2012-workshop/

Ok, back to work philosophico-engineering the future social web :-)

Henry


> 
> Larry
> --
> http://larry.masinter.net
> 
> 
> 
> 
> 
> 

Social Web Architect
http://bblfish.net/

Received on Wednesday, 11 April 2012 12:06:14 UTC