# Re: blow away?

cmenzel@kbssun1.tamu.edu (Chris Menzel)
From: cmenzel@kbssun1.tamu.edu (Chris Menzel)
Message-id: <9309141937.AA12027@kbssun1.tamu.edu>
Subject: Re: blow away?
To: phayes@cs.uiuc.edu
Date: Tue, 14 Sep 1993 14:37:56 -0500 (CDT)
Cc: interlingua@ISI.EDU
In-reply-to: <199309141905.AA04418@dante.cs.uiuc.edu> from "phayes@cs.uiuc.edu" at Sep 14, 93 02:08:23 pm
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Pat Hayes writes:
: John Sowa writes-
:
: >.... The only thing that any of us are proposing is a version
: >of first-order logic with a LISP-like and a graph-like notation.
: >If anyone else prefers some other notation, they're welcome to
: >design it, as long as it maps to the same semantic base.
:
: The trouble with this is that we know pretty clearly that first-order
: logic is inadequate as a semantic base. We need more expressive (or
: perhaps just differently expressive) languages to do a good job of
: knowledge representation. I bet we need some higher-order
: expressibility,...
Certainly true in the sense that we need to be able to talk about
"higher-order" objects like properties- and relations-in-intension in
addition to more mundane entities. What is less clear is whether it
is necessary to go all the way to a full-blown higher-order logic,
i.e., with quantification over (some intensional counterpart of) the
full power set of (in general, the nth cartesian product of) the
domain of individuals, where we lose completeness and most of those
other nice, friendly properties of first-order logic. At any rate,
because of this it would seem to be sound methodologically as far as
possible to try to satisfy the needs of KR with first-order extensions
to classical FOL.
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Christopher Menzel Internet -> cmenzel@tamu.edu
Philosophy, Texas A&M University Phone ----> (409) 845-8764
College Station, TX 77843-4237 Fax ------> (409) 845-0458
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