W3C home > Mailing lists > Public > www-rdf-interest@w3.org > January 2001

Re: Proposal: variables, templates, and Stickey Cyber Molecules

From: Seth Russell <seth@robustai.net>
Date: Fri, 19 Jan 2001 13:40:26 -0800
Message-ID: <3A68B44A.C4E73C62@robustai.net>
To: fmanola@mitre.org
CC: www-rdf-interest@w3.org
Frank Manola wrote:

> Seth Russell wrote:
> >
> > This is where I think we need to draw a distinction between internal and external.
> > Most implementations assign a unique identifier to any node they create (anonymous
> > or not); the question, I think, is whether it is wise to publish that unique
> > identifier to the outside world as a URI.  I would weigh in on the side that it is
> > not.
> It seems to me there are a couple of issues here (on the other hand, I
> may be misunderstanding what the "universal" in "URI" means).  One is
> the implication of using the word "publish" in the quotation above.  I
> may be wrong, but just because you assign a resource a URI doesn't
> necessarily mean the URI gets (or ought to be)
> published/widely-distributed.

Yes, certainly, and that was my point.  How widely it is distributed is not the point,
anything that is outside of the boundary of the running application would, in my way of
thinking, be publishing.

> It's just that the resource is uniquely
> identified within a universal scope.

I think your term "universal scope" is mischosen here.  If it is not published to the
external world (or read from the external world) than the scope of this unique identifier
is the boundary of the local system; whatever that may be; for example it might be a
database on a personal computer.   The scope is the internal data of a single running
application.  This scope cannot be considered "universal".

> There are certainly lots of Web
> resources whose URLs aren't widely published, or which are only
> accessible from within a given context (using a loose definition of
> "context").


> That's a question of access control rather than unique
> identity.

The restriction of access control restrains the uniqueness of the identity to the scope
of the local system.  It could get a bit philosophical at this point, hopefully we won't
need to and you will see where I am going;  otherwise we might need to wake up the late
Willard Van Orman Quine.

> So I think your distinction between internal and external (we
> could even have varying degrees of internalness/externalness) is a good
> one, but that seems to me distinct from whether you can use URIs for
> "internal" references or not.

Well yes I agree.  Internally within our system we must be able to dereference our
pointers,  therefore we must have unique identifiers.  If I say [:Socretes a :Man] and
then add later  [:Man :hasProperty :Mortal], the only way I can get from :Socretes to
:Mortal is via the unique identifier :Man.  But it need only be unique internally to my
local system .... it's quite a different animal from the URI.

> It's going to have to arise one way or another.  Certainly if we're
> going to identify things in the world (as opposed to Web pages stored in
> specific files in computers) using URIs, there really doesn't appear to
> be any way to keep people (or computers) from using and publishing
> multiple URIs that turn out to identify the same thing, unless we have a
> lot of very strict regulation by registration authorities that people
> don't seem to want.

I agree, but How?

Seth Russell
Received on Friday, 19 January 2001 16:33:32 UTC

This archive was generated by hypermail 2.3.1 : Wednesday, 7 January 2015 15:07:34 UTC