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Re: a simple question

From: Drew McDermott <drew.mcdermott@yale.edu>
Date: Fri, 5 Dec 2003 13:38:48 -0500 (EST)
Message-Id: <200312051838.hB5Icmu27986@pantheon-po04.its.yale.edu>
To: www-rdf-rules@w3.org


   [Dan Connolly]
   I suggest that checkable valid conclusions are
   essential to anarchic scalability.

A fond wish, but one that can't be granted.

Suppose a web service offers a warehouse-truck scheduling algorithm.
The algorithm is widely used and endorsed by several major truckers,
but it comes with no optimality guarantee.  Your agent uses the output
of the algorithm as one step in an inference concerning a
preventive-maintenance schedule for your trucks for next month.

In what sense are the outputs of the algorithm checkable _or_ valid?

I fear that this is the usual case, not an outlier.  That's why
"undisciplined" use of negation-as-failure doesn't scare me.  It's
just allowing useful heuristicism to appear in small doses amidst
logical inferences, on the grounds that the logical inferences will
mainly be glue between large-scale computations permeated with
heuristicism.

Maybe this is a good way to think about it: Many inferences are
justified by statements of the form, "Here's my conclusion and my
grounds for believing it; just try to refute it."  That is, checking
is not just a matter of verifying that each step is actually justified
by an inference rule.  It can also be a matter of trying to find a
better conclusion than the one offered.

   I wish I could elaborate, but I'm juggling too many
   things just now. I hope you don't mind my using
   your inboxes to bookmark my thought.

   The relevant wiki nodes are these, though I don't
   think they make my point quite yet either:

     http://esw.w3.org/topic/AnarchicScalability
     http://esw.w3.org/topic/SemanticWebBus

I will take a look.

                                             -- Drew

-- 
                                             -- Drew McDermott
                                                Yale University CS Dept.
Received on Friday, 5 December 2003 13:38:49 GMT

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