Re: Classes and predicates as first class objects

Although the cited documentation page does not contain an example of
quantification over predicates in CycL, here is one:

(implies
       (and
           (genlPreds ?PRED ?GENL-PRED)
           (?PRED ?ARG1 ?ARG2))
       (?GENL-PRED ?ARG1 ?ARG2))

which Cyc paraphrases into English as:

If ?PRED is a specialized form of ?GENL-PRED and PRED holds of some ARG1
and some ARG2, then GENL-PRED holds of ARG1 and ARG2.

Much more documentation on Cyc can be found at
http://www.opencyc.org/doc

-Steve

On Thu, 15 Aug 2002, Peter F. Patel-Schneider wrote:

>
> From: "R.V.Guha" <guha@guha.com>
> Subject: Classes and predicates as first class objects
> Date: Wed, 14 Aug 2002 14:19:56 -0700
>
> [...]
>
> >  RDF, which has been largely influenced by the experimental "scruffy"
> > side of AI has gone the route of many experimental AI systems (starting
> > from KRL, RLL, .... CycL) and incorporated these as first class objects.
>
> [...]
>
> Hmm.  It appears to me that CycL does *not* treat predicates as first-class
> objects,  In particular, the syntax for CycL at
> http://www.cyc.com/cycl.html appears to disallow quantification over
> predicates.
>
> peter
>
>
>

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Received on Thursday, 15 August 2002 13:06:31 UTC