RE: ONT RE: Ontology case study
ChrisM,
But what is the logical status of "Drinks(john)"?
It seems to me to need some more work. Surely John needs to be indexical to
work. If I am John then this may be true, if John is someone else it does
not seem to logically follow. I am not sure that "e.g., operators that can
form proposition-denoting terms from sentences. " buys you this - but would
be pleased if it did. Can you explain?
It seems to me that databases systems can do 'practical reasoning', but
cannot explain how (a serious crime in academic circles?), whereas FOL does
not - but can explain what it does.
ChrisP
-----Original Message-----
From: owner-ontology@majordomo.ieee.org
[mailto:owner-ontology@majordomo.ieee.org]On Behalf Of Chris Menzel
Sent: 30 May 2002 01:03
To: Chris Partridge
Cc: ontology@ieee.org
Subject: Re: ONT RE: Ontology case study
On Wed, May 29, 2002 at 05:31:28PM -0500, I wrote:
> If, however, you simply take a practical syllogism to end in a
> conclusion that *specifies* an action, or a judgment or decision about
> a course of action, then of course FOL can "do" practical reasoning,
> e.g.,
>
> John wishes to slake his thirst.
> John believes that by taking a drink he'll slake his thirst.
> Therefore, John takes (or decides to take, or ought to take) a drink.
I didn't say enough here. What ChrisP said is true in the sense that
standard FOL requires supplementation with further operators in order to
represent arguments like the above, e.g., operators that can form
proposition-denoting terms from sentences. My point is that this can be
done in a first-order context. For example, suppose we let [...] be an
operator that forms terms of the sort just mentioned. Then, taking
John's thirst to be something we can refer to (a state of John, or some
such thing), the argument above can be rendered as:
Wishes(john,[Slaked(thirst-of(john))])
Bel(john,[Drinks(john) -> Slaked(thirst-of(john))])
Drinks(john)
Or something like that.
-chris