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Re: A plea for peace. was: RE: DAML+OIL (March 2001) released: a correction

From: Aaron Swartz <aswartz@swartzfam.com>
Date: Thu, 12 Apr 2001 12:35:22 -0500
To: pat hayes <phayes@ai.uwf.edu>
CC: RDF Logic <www-rdf-logic@w3.org>
Message-ID: <B6FB407F.9043%aswartz@swartzfam.com>
pat hayes <phayes@ai.uwf.edu> wrote:

>>> All objects? There are objects which have no name in any human
>>> language.
>> That doesn't prevent you from giving them one.
> That doesnt prevent it, but there might well be circumstances which
> do prevent you from giving them one. Obviously we can, and often do,
> refer to things that we cannot possibly give a name to (since we
> cannot identify them), eg as when we say that a beach contains
> hundreds of billions of grains of sand, each consisting largely of
> silica. It is (literally) impossible to give a name to every grain.

Is it really impossible? Hmm, how about we say that I define:


where n is the number of the grain of sand on the shore of Lake Michigan,
USA, numbered depth first, from top to bottom and left to write currently
existing at the precise moment in time that I click send on this message.
Now I've given them all names. Sure, it may be extremely, extremely
difficult (I'm not sure that it is actually impossible) to go from one of
these names to the actual grain of sand, but that does not mean that I have
not given them all a name.

> (Similarly leaves of a tree, bacteria in a Petri dish, stars in a
> remote galaxy, hydrogen atoms, etc. etc. .)

Leaves of a tree are actually much easier to deal with, since they are large
enough to write their URIs on. Others can be dealt with in a similar way to
the sand, probably even more precisely, since they are commonly used in
scientific work.

>> There is no authority to define the
>> "meaning" of a word. However, it is clear who defines the meaning of a URI
>> -- its "owner".
> Ah, that is an interesting claim. Is it so clear?

Well, it is clear that the owner holds the authority. However, I did not
claim that it was clear who the owner was, or their definition was clear.

> First, if the 
> "owner" is a human being, then maybe one could claim this; but even
> then, how does anyone else find out what meaning the "owner" had in
> mind (barring telepathy)?

Well, we ask them, of course. Now I admit, this is not an exact way of
finding out the meaning, but I know of none better. I'm sure that if you
have a better way of discovering meaning it could be worked in. Until then,
we'll have to do with what we have.

> And how do we know that the "owner" had a
> single clear idea in mind? The owner may be confused about the
> meaning, and if the word is part of a piece of natural language text
> (eg inside HTML) then it is just as vague and nuanced in its meaning
> as any other word in natural language.

Well, it's not a word -- it's a URI. The meaning of the resource represented
by the URI is defined by its owner. The owner may be confused, I admit, but
at least we have limited our definition to a single person (at least I'm
pretty sure it will be a person) who can give a definitive answer. This is
better than some vague amorphous entity that depends on the ever-changing
feelings of society at large (current natural language words). Again, if
you've got something better, please let us know. Until then, this system
seems to work pretty well.

> And in any 
> case, what if the "owner" is, say, a refrigerator, or a file system?
> Your use of scare quotes suggests that you are aware of such cases.

The quotes I used were to ensure that it wasn't confused with some sort of
legal definition of ownership, etc. I think it is unlikely within the near
future that we will see refrigerators with advanced enough Artificial
Intelligence that they will begin to create URIs of their own will. If that
happens, then I suppose we can simply ask the refrigerator, as we would ask
any other person. In many cases however, a refrigerator is simply a machine
carrying out work on behalf of its programmer, which often delegates
responsibility to the owner of the machine.

>> This may not be a rigorously mathematical system, I admit, but it
>> has worked well enough for the millions of users of the Web.
> Sigh. This discussion seems to to constantly be going around this
> particular loop, which is starting to get frustrating.
> Yes, of course. It works for the millions of HUMAN users of the Web.
> This is not surprising, since names (not URI's, just plain names)
> have worked for the hundreds of millions of human beings who have
> been using language since before the Neolithic. (The Web hasnt added
> anything to the human use of language; it has just enabled us all to
> listen to more of it.) But this entire discussion on RDF is about how
> to arrange things so that SOFTWARE AGENTS can use information on the
> web, not human beings.

Of course! But, to my knowledge, these SOFTWARE AGENTS are all programmed
and run by HUMAN BEINGS (or at least, there is always a human at the top of
the chain of command). The reason we seem to keep going in this loop is
because I don't see what's better. I know of no language that conveys
"knowledge" to machines. Instead, the best we can do is use human language
to invent a more rigorous one, and build up from there. But unless you know
something I don't, there will always be human agreement and human language
at the bottom. I simply don't see any other way.

If I'm missing something, please tell me what this powerful language is. I'd
love to get my hands on it.

[ Aaron Swartz | me@aaronsw.com | http://www.aaronsw.com ]
Received on Thursday, 12 April 2001 13:35:35 GMT

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