Re: Meaning

Drew McDermott wrote a very interesting contribution, which I shan't
attempt to respond to point-by-point and instead shall summarise as
follows:

1. Precise formal semantics for real-world terms such as "owns" aren't
   necessary to build the Semantic Web (and we aren't likely to get them
   anyway).

2. We can cease worrying and go ahead using such terms in formal languages
   that are reasoned over by machine agents even without precise and
   complete definitions.

I mostly agree with Item 1.  In particular, I think it's worth referring
to Cyc's notion of context, true-in-context, and reasoning-within-contexts
as the best attempt I know of (to date) to capture the real-world
complexity of concepts such as "owns."  I think Prolog and Prolog-esque
languages (here I would include all subject-predicate-object or FOPL-like
languages, including DAML and OWL) are hopelessly doomed when attempting
to capture sophisticated conditional and contextual notions.

To sum up: you simply cannot reduce reality to a set of formalized
universal and existential predicates.

Which brings me to point 2.  Can we, or can we not, proceed?  The point of
the Semantic Web, as I understand it, is to enable real people to use
machine augmentation to assist their real world tasks using the Web's
resources.  Can an agent with this level of understanding do that?

I would like the answer to be "yes" but I fear it is "no," though not for
any technical reasons.  Let us briefly take the case of a business that
wishes to buy widgets.  We must convince the financial officers of the
company (not the techies, mind you) that we can produce a system of
sufficiently sound and complex reasoning that it can go out on the Web,
find, and purchase widgets for their company.  That is, spend real money
on real things.

And we must build such a system knowing that it has an imbecile's notion
of "own" and "buy" and simply no concept whatsoever of "fraud" or
"deceit."

I imagine this to be a *very* hard sell.

-- 
--Alan Wexelblat
wex@media.mit.edu		http://wex.www.media.mit.edu/people/wex/
"The liberties of a people never were, nor ever will be, secure when the
transactions of their rulers may be concealed from them." -- Patrick Henry

Received on Friday, 23 May 2003 10:57:48 UTC