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RE: What do the ontologists want

From: pat hayes <phayes@ai.uwf.edu>
Date: Fri, 18 May 2001 15:10:31 -0500
Message-Id: <v0421012fb72b31498c35@[]>
To: "Emery, Pat" <pemery@grci.com>
Cc: www-rdf-logic@w3.org
>I was looking at it as it is a belief the sky is blue versus a fact the sky
>is blue.
>For example if there was a package that I believed would fit through the
>I believe it by "eyeballing" up the size of the package and the door.
>I would assert Believe(I, (the package will fit through the door)) versus I
>have taken
>exact measurements of the package or actually tried to put the package
>through the door.
>In the later cases I would assert (the package will fit through the door).
>It just seems to me that since people find the need to draw this distinction
>believing and knowing that the agents should find value in that as well.

OK, fair enough. I think that the belief/know distinction is chiefly 
of use in evaluating other believer's mental states than one's own, 
at least until we get to the point where our software agents can be 
said to have something like a psychology; but I was really only 
meaning to explain why I had made the simplification in the example. 
You are right, the more accurate translation is as you describe.

This makes no difference to the general point about reification, of 
course, since subexpressions of modal expressions are not reified 

Pat Hayes

>-----Original Message-----
>From: pat hayes [mailto:phayes@ai.uwf.edu]
>Sent: Thursday, May 17, 2001 7:16 PM
>To: Emery, Pat
>Cc: Graham Klyne; www-rdf-logic@w3.org
>Subject: RE: What do the ontologists want
> >Pat hayes wrote:
> > >>  'Jon says "The sky is blue"'
> > >>  'I believe Jon'
> > >>=>
> > >>  'I believe (the sky is blue)'
> >
> > >Careful, those are two different senses of 'believe'. You don't
> > >believe Jon is TRUE, right? You believe that what he SAYS is true.
> > >Write that out and your example looks more, er, logical:
> > >
> > >Says(Jon,  (the sky is blue))
> > >Says(Jon, ?p) implies ?p.
> > >=>
> > >(the sky is blue)
> >
> >Shouldn't it be something more like:
> >
> >Says(Jon, (the sky is blue))
> >Says(Jon ?p) implies Believe(I, ?p))
> >=>
> >Believe(I, (the sky is blue))
>Yes, that would more accurately transcribe the example. I tend to
>assume that since "I" means the one who is manipulating the beliefs,
>as it were, that Believe(I, ?p) is pretty much interderivable with
>plain ?p.  After all, if ?p is something I am asserting, then
>presumably I believe that ?p, and then I would have to be pretty
>cynical about myself not to be willing to conclude from this that
>Believe(I, ?p); and contrariwise if I believe that Believe(I,?p),
>(and am not just trying to lie to my God, say), then I ought to be
>willing to conclude ?p. I guess there might a kind of existential
>state of self-doubt that would block this inference, but I do not
>want to make neurotic web software agents just yet.
>Pat Hayes
>IHMC					(850)434 8903   home
>40 South Alcaniz St.			(850)202 4416   office
>Pensacola,  FL 32501			(850)202 4440   fax

IHMC					(850)434 8903   home
40 South Alcaniz St.			(850)202 4416   office
Pensacola,  FL 32501			(850)202 4440   fax
Received on Friday, 18 May 2001 16:10:30 UTC

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