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AIList Digest Volume 8 Issue 103
AIList Digest Tuesday, 11 Oct 1988 Volume 8 : Issue 103
Philosophy:
State and change/continuous actions
Continuity and computability
Belief and awareness
Intelligence / Consciousness Test for Machines (Neural-Nets)???
The Grand Challenge is Foolish
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Date: 26 Sep 88 12:18:24 GMT
From: steve@hubcap.UUCP ("Steve" Stevenson)
Subject: Re: state and change/continuous actions
>From a previous article, by smryan@garth.UUCP (Steven Ryan):
>
> Continuous systems are computably using calculus, but is this `effective
> computation?' Calculus uses a number of existent theorems which prove some
> point or set exists, but provide no method to effectively compute the value.
Clearly numerical analysis emulates continuous systems. In the phil of
math, this is, of course, an issue. For those denying reals but
allowing the actual infinity of integers, NA is as good as the Tm.
Not only are there existence theorems for point sets, but such theorems
as the Peano Kernel Theorem are effective computations. At the point
set level, one uses things called ``simple functions''.
BTW, you're being too restrictive. There are many ``continuous'' systems which
have a denumerable number of points of nondifferentiablity: there
are several ways to handle this (e.g., measure theory). These are
not ``calculus'' in the usual sense. Important applications are in diffusion
and probability. So, is Riemann-Stiltjes the only true calculus? Nah.
There's one per view.
--
Steve (really "D. E.") Stevenson steve@hubcap.clemson.edu
Department of Computer Science, (803)656-5880.mabell
Clemson University, Clemson, SC 29634-1906
------------------------------
Date: Mon, 3 Oct 88 13:49:33 GMT
From: Mr Jack Campin <jack%cs.glasgow.ac.uk@NSS.Cs.Ucl.AC.UK>
Subject: continuity and computability
smryan@garth.UUCP (Steven Ryan) wrote:
>> "Insufficient attention has been paid to the problem of continuous
>> actions." Now, a question that immediately comes to mind is "What problem?"
> Continuous systems are computable using calculus, but is this `effective
> computation?' Calculus uses a number of existence theorems which prove some
> point or set exists, but provide no method to effectively compute the value.
> It is not clear that all natural phenomena can be modelled on the discrete
> and finite digital computer. If not, what computer could we use?
I brought up this same point in the Usenet sci.logic newsgroup a short while
ago. There is a precise sense in which analogue computers are more powerful
than digital ones - i.e. there are continuous phenomena unsimulatable on a
Turing machine.
Most of the work on this has been done by Marian Pour-El and her coworkers.
An early paper is "A computable ordinary differential equation which possesses
no computable solution", Annals of Mathematical Logic, volume 17, 1979, pages
61-90. This result is a bit of a cheat (the way the equation is set up has
little relation to anything in the physical world) but I believe later papers
tighten it up somewhat (one uses the wave equation, which you'd expect to be a
powerful computing device given that interferometers can calculate Fourier
transforms in constant time). I haven't seen these later articles, though.
--
Jack Campin, Computing Science Department, Glasgow University, 17 Lilybank
Gardens, Glasgow G12 8QQ, SCOTLAND. 041 339 8855 x6045 wk 041 556 1878 ho
ARPA: jack%cs.glasgow.ac.uk@nss.cs.ucl.ac.uk USENET: jack@glasgow.uucp
JANET: jack@uk.ac.glasgow.cs PLINGnet: ...mcvax!ukc!cs.glasgow.ac.uk!jack
------------------------------
Date: 5 Oct 88 17:59:14 PDT
From: "Joseph Y. Halpern" <HALPERN@ibm.com>
Subject: Belief and awareness
In response to Fabrizio Sebastiani's question of Sept. 23 regarding
further work on Fagin and my notion of "awareness", here is what I am
aware of: (a) Kurt Konolige wrote a critique of the paper which appeared
in the proceedings of the 1986 Conference on Theoretical Aspects of
Reasoning About Knowledge; (b) Robert Hadley wrote a critique (and
discussed other ways of dealing with the problem) which appeared as a
Tech Report at Simon Fraser University (the exact reference can be found
in the journal version of our paper, which appears in Artificial Intelligence,
vol. 34, pp. 39-76); (c) Yoram Moses provided a model for polynomial time
knowledge, which can be viewed as a notion of awareness; Yoram's paper
appears in the proceedings of the 1988 Conference on Theoretical Aspects
of Reasoning About Knowledge; (d) Mark Tuttle, Yoram Moses, and I have
a paper in the 1988 Symposium on Theory of Computing which focuses
on zero-knowledge protocols, but also extends Yoram's definitions
to deal with learning. -- Joe Halpern
------------------------------
Date: 9 Oct 88 12:54:39 GMT
From: TAURUS.BITNET!shani@ucbvax.berkeley.edu
Subject: Re: Intelligence / Consciousness Test for Machines
(Neural-Nets)???
In article <1141@usfvax2.EDU>, mician@usfvax2.BITNET writes:
>
> When can a machine be considered a conscious entity?
>
Oh no! not that again! ;-)
Okay, I'll make it short and somewhat cyinc this time: The answer is: NEVER!
You see andy, the only reason for you to assume that there is such a thing as
a conscious entity at all, is that otherwise, YOU are not a conscious entity,
and that probebly sounds nonsense to you (Actualy when saying that, I already
take a dangerious step forward, assuming that YOU ARE... the only thing I can
know is that I AM a conscious entity...).
I hope that helps...
O.S.
------------------------------
Date: 9 Oct 88 18:21:51 GMT
From: uwslh!lishka@spool.cs.wisc.edu (Fish-Guts)
Reply-to: uwslh!lishka@spool.cs.wisc.edu (Fish-Guts)
Subject: Re: The Grand Challenge is Foolish
In article <ohbWO@SAIL.Stanford.EDU> JMC@SAIL.STANFORD.EDU writes:
>[In reply to message sent Mon 26 Sep 1988 23:22-EDT.]
>If John Nagle thinks that "The lesson of the last five years seems to
>be that throwing money at AI is not enormously productive.", he is
>also confusing science with engineering. It's like saying that the
>lesson of the last five years of astronomy has been unproductive.
>Progress in science is measured in longer periods than that.
I don't think anyone could have said it better. If AI is going
to progress at all, I think it will need quite a bit of time, for its
goals seem to be fairly "grand." I think this definitely applies to
research in Neural Nets and Connectionism: many people criticize this
area, even though it has only really gotten going (again) in the past
few years. There *have* been some really interesting discoveries due
to AI; however, they have not been as amazing and earth-shattering as
some would like.
In my opinion, the great amount of hype in AI is what leads many
people to say stuff such as "throwing money at AI is not enormously
productive." If many scientists and companies would stop making their
research or products out to be much more than they actually are, I
feel that others reviewing the AI field would not be so critical.
Many AI researchers and companies need to be much more "modest" in
assessing their work; they should not make promises they cannot keep.
After all, the goal of achieving true "artificial intelligence" (in
the literal sense of the phrase) is not one that will occur in the
next two, ten, fifty, one-hundred, or maybe even one-thousand years.
.oO Chris Oo.
--
Christopher Lishka ...!{rutgers|ucbvax|...}!uwvax!uwslh!lishka
Wisconsin State Lab of Hygiene lishka%uwslh.uucp@cs.wisc.edu
Immunology Section (608)262-1617 lishka@uwslh.uucp
----
"...Just because someone is shy and gets straight A's does not mean they won't
put wads of gum in your arm pits."
- Lynda Barry, "Ernie Pook's Commeek: Gum of Mystery"
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End of AIList Digest
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