 Robots with an inner life? Hans Moravec, robot visionary extraordinaire, says they're just around the corner. And you might even be one of them. |
For some people, mere mention of the
word "robot" is enough to set the pulse racing. I am not one of
them. For me, robots are things that dwell in the banal literary
culture of science fiction and in the lonely fantasies of computer
hackers who long to be able to wake up in the morning and utter the
words, "Well, what shall we do today, my mechanical friend?"
As a little boy growing up in his native Austria and then in Canada,
Hans Moravec tinkered with toy robots and was haunted by the thought
that he himself might be a robot. But Moravec is no ordinary robotics
freak. Director of the Mobile Robot Lab at Carnegie-Mellon, he is a
formidably clever fellow with a philosophical ax to grind--several
axes, in fact. For one thing, he is an avowed Platonist. For another,
he is a pan-psychist, a believer in the doctrine that consciousness
infiltrates all matter. And, on the evidence of his writings, I think
he might also be an undiagnosed Orphic.
In the reviewer's cliche, Moravec has written two books in
Robot. One of them is a sober account of what has been been
going on over the last couple of decades in robotics and artificial
intelligence (AI)--fields in which the author ranks among the most
accomplished and controversial figures. The other is a lotus-eating
exercise in futurology and speculative metaphysics that sometimes left
me breathless and sometimes made my flesh creep.
Let's take the sober book first. It is informative and also comes as
something of a relief: If you haven't been paying attention to Al and
robotics in recent years, you haven't missed a great deal. From the
beginning, both endeavors have been long on hyperbole and short on
results, though Moravec is not always candid in acknowledging this. In
the 1950s, the future Nobel laureate Herbert Simon bragged that by
getting a computer to deduce some theorems in elementary geometry, he
had solved the mind-body problem. In 1970 a robot called Shakey was
dubbed "the first electronic person" by Life
magazine. Assembled by Stanford scientists, Shakey was a square
cabinet on wheels with a TV camera and range finder mounted on top. On
a good day the contraption could haltingly make its way down a
straight corridor. "In from three to eight years we will have a
machine with the general intelligence of an average human being,"
blustered Marvin Minsky, the father of Al.
Nothing of the sort has happened.despite the best efforts of
scientists like Moravec. Arriving at the Stanford Al lab in 1971, he
started working on a successor to Shakey. By the end of the decade the
new robot was able to negotiate the rolling adobe outside the lab for
about fifteen meters before becoming paralyzed with confusion. "Only
in the 1990s" Moravec writes, "did complex mobile robots really begin
to show some promise. Today there are dozens of wastebasket-sized
machines wandering the halls of universities and other research
institutions all over the world" Toss in a hundred thousand or so
industrial robots performing repetitive assembly-line work like spot
welding--but lacking sufficient consciousness to feel alienated from
the product of their labor--and that's about it.
Why such pitiable progress? There are three reasons. First, the
hardware. To get a computer with as much raw power as the human brain,
you'd have to wire together a few dozen versions of the IBM Deep Blue
machine that defeated Garry Kasparov in chess last year, and that
would make for a rather gargantuan automaton. Admittedly, this may
only be a temporary problem: Moravec predicts that brain-sized
computers of brain-sized power will be available within two
decades.
The second and more formidable obstacle is software. A robot worth the
name must be able to perceive its environment, manipulate it, and
reason about it. It took natural selection a billion years or so to
engineer human vision. If you think mimicking that faculty in computer
code is easy, Moravec's account of his own frustrations will disabuse
you. Deep Blue could beat Kasparov, but no computer today, however
festooned with sensors and servomechanisms, can do what any child can:
move the chess pieces from square to square. And things are no better
when it comes to reasoning, thanks to the notorious "frame problem."
The most trivial inferences we make in everyday life involve
background knowledge that potentially extends to the whole of human
culture. The programmer who tries to represent this formally is faced
with what Moravec calls a "combinatorial explosion" of facts
interacting with facts. The context of the computer's reasoning must
therefore be artificially limited to a "frame" of manageable size.That
is why Al software shows no common sense-- why, for example, the best
medical expert program will prescribe penicillin for a broken
bicycle.
Finally, there is the matter of economic incentive. What profit is
there in a robot that can do everything a human can? We already have
complex, easily programmable, nonlinear servomechanisms that can be
cheaply and easily reproduced by unskilled labor: us!
This isn't good enough for Moravec. He is unhappy having to inhabit an
imperfectly designed body compounded of lime and jelly. "I resent the
fact that I have these very insistent drives which take an enormous
amount of effort to satisfy and are never completely appeased." he
once told a reporter. Ten years ago. he wrote a book called Mind
Children that described how we might shuffle off this mortal coil
by downloading our minds into computers. A reviewer in The
Washington Post called it "the most lurid book ever published by
Harvard University Press." But this idea is not really so lurid. It is
just the latest manifestation of the ancient cult of Orpheus. Our true
life is among the stars, Orphism holds, but we are tied to the earth
by our bodies; only by purifying and renouncing these bodies can we
attain to the highest ecstasies. Though Moravec does not call himself
an Orphic, this is precisely his philosophy, right down to his talk of
our souls "transmigrating" into immortal robots.
In the latter chapters of Robot--the lotus-eating part--Moravec
elaborates on his vision in bold, and surprisingly compelling,
detail. He begins by sketching out the four generations of robots that
will supposedly evolve between now and the middle of the next
century.They will have the cognitive powers, respectively, of lizards,
mice, monkeys, and, finally, men. By the year 2040, he claims, robots
will not only be able to reason about the world by simulating it, they
will also be able to reason about their simulations. In short, they
will have an inner life.
I have the gravest doubts about these projections, but I am willing to
crush them for the sake of entertaining what comes next: the end of
capitalism (as the marginal value of human labor drops to zero), the
transformation of physical space into cyberspace (as all matter is
pressed into computational service), and the blurring of personal
identities in a permanent orgy of experiential simulation. Now,
Moravec's scenario of the future is unabashedly conjectural and even
verges on science fiction.Yet it is all rooted in his sophisticated
knowledge of physics and engineering.
And Moravec does not stint on the engineering details. He is already
famous fur his conception of a robot with repeatedly branching arms
that terminate in trillions of microscopic fingers capable of
manipulating matter at the atomic level: a sort of fractally
structured, animated bush. Here he generalizes the idea to robots with
physically discontinuous parts smaller than dust motes that are
powered and controlled by light beams. As is frequently the case with
bravura engineering, a certain visual poetry emerges: Such a being, he
writes, would appear to be "surrounded by an illuminated cloud that
does its bidding as if by magic."
It is only when Moravec ventures into metaphysics that his logic gets
wonky."But what is consciousness?" he asks on one page. "What is
reality , anyway?" he asks on the next. He has already told us that he
leans toward "physical fundamentalism"-- the dogma that only physical
science deserves the title of true knowledge and that "other belief
systems may have social utility for the groups that practice them,but
ultimately they are just made-up stories." Presumably, then, the
answers he proffers to these philosophical questions are to be taken
in the spirit of "made-up stories."
Still, they won't have much social utility for philosophers. If minds
can be extracted from brains and put into computers, as Moravec
believes, then consciousness must be no more than the running of a
very complicated software program. What the hardware happens to
be--squishy neurons,hard silicon--doesn't really matter.
This theory of mind, called functionalism, used to be fashionable
among philosophers and philosophically inclined cognitive scientists,
but it has fallen into disrepute in the last decade. One of the
problems with it was pointed out by the philosopher Hilary Putnam, who
showed that any system with nonrepeating states--a waterfall,
say--can be interpreted as a computer running any program you
please. (Think of the physical states of the waterfall as an unending
series of random numbers; depending on how this series is interpreted,
It can be seen as encoding anything from the consecutive positions of
the planets, to the complete works of Shakespeare, to the functioning
of your next-door neighbor's mind.) So unless we are willing to
attribute consciousness to waterfalls, we had better drop the notion
that computation alone creates mind.
Moravec would rather attribute consciousness to waterfalls. He is, he
says, a Platonist, and "Platonism holds that the soul is in the
abstract relationships represented, not the mechanics of how they are
encoded." Since the soul is just a mathematical object, a program,
that anything sufficiently complex can be interpreted as encoding, it
must follow that "anything can be interpreted as possessing
... consciousness and intelligence"--even, Moravec cheerfully
concedes, a rock. It gets better. Since Interpretations too are
mathematical entities, Platonically out there, the rock's
consciousness is just as real as ours. Moravec, in short, turns out to
be a pan-psychist.
And who's to say he is wrong? I, for one, wouldn't know how to go
about proving that every object in the universe doesn't have a
mind. But if this is true, I fear that the heroic labors of our
robotic "mind children" in Moravec's futurological vision will be in
vain. Why make the universe into mind, or at least a cosmic version of
Bill Gates's house, if it already is mind?
Still, no reader will want to miss out on Moravec's clairvoyant
perception of tomorrow's universe "teeming with unhuman superminds,
engaged in affairs that are to human concerns as ours are to those of
bacteria." Contemplating the Great Cosmic Revel to come, I was
gloomily reminded that I would probably be dead before my mind could
be downloaded into a vintage 2050 robot, and hence, unlike some of my
younger friends, I would miss out on the eternal cyberparty promised
by Moravec.
Born too soon, born too soon.