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Chapter 12
Hal 9000 and AI
Hal 9000, an intelligent computer system, plays
an important part in the novel “2001: A Space
Odyssey” written by Arthor Clark, published
for the first time in 1968.
This novel was later made into a film, directed
by Stanley Kubrick, also in 1968.
The following figure shows the eyes of Hal 9000.
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What is the story?
Below is a much simplified plot summary of
this film, emphasizing the role played by Hal 9000:
“When the world is ruled by apes, one
particular group discovers a mysterious
rectangular monolith near their home.
Astronaut David Bowman, along with
four companions, sets off for Jupiter on
a spaceship controlled by HAL 9000, a
revolutionary computer system that is
every bit mankind’s equal, and perhaps
his superior.
When HAL endangers the crew’s lives
for the sake of the mission, Bowman
will have to first overcome the computer, then travel to the birthplace of
the monolith.”
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What does Hal 9000 do?
The following is a scenario as depicted in the
novel, where Hal 9000 tries to take control of
the spaceship:
“Hal, switch to manual hibernation
control.”
Question: How does Hal 9000 understand
Dave’s command? What kind of ability should
Hal possess to distinguish different people’s
voice?
“I can tell from your voice harmonics,
Dave, that you’re badly upset. Why
don’t you take a stress pill and get some
rest?”
Question: How can Hall 9000 tell Dave is upset from the harmonics of his voice? Moreover,
now can Hal make the prescription for Dave?
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“Hal, I am in command of this ship.
I order you to release the manual hibernation control.”
Question: How does Hal tell the difference
between “order” and “request”?
“I’m sorry, Dave, but in accordance
with special subroutine C1435-dash-4,
quote, When the crew are dead or incapacitated, the onboard computer must
assume control, unquote. I must, therefore, overrule your authority, since you
are not in any condition to exercise it
intelligently.”
Question: What is “C1435-dash-4”? How
does Hal remember its content? How does Hal
find such a special routine that is immediately
applicable? Is the reasoning that Hal just made
sound? Is it rule based?
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“Hal,” said Bowman, now speaking
with an icy calm. “I am not incapacitated. Unless you obey my instructions, I shall be forced to disconnect
you.”
Question: Can Hal tell the “icy” tone of Bowman?
“I know you have had that on your
mind for some time now, Dave, but
that would be a terrible mistake. I am
so much more capable than you are of
supervising the ship, and I have such
enthusiasm for the mission and confidence in its success.”
Question: How can Hal know that Bowman
has this tough in his mind for a while? How
does Hal rich the conclusion that Bowman might
make a terrible mistake? Will you do the same?
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“Listen to me very carefully, Hal. Unless you release the hibernation control
immediately and follow every order I
give from now on, I’ll go to Central and
carry out a complete disconnection.”
Hal’s surrender was as total as it was
unexpected. “O.K., Dave,” he said.
“You’re certainly the boss. I was only
trying to do what I thought best. Naturally, I will follow all your orders. You
now have full manual hibernation control.”
Question: What is the Achilles heel of Hal 9000?
Is this really fatal to Hal 9000? What happens
if he carries battery? How do we control such
a powerful companion if the need arises?
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Hal 9000’s ability
It is obvious that Hal 9000 is able to “listen”,
“think”, and “talk” to people in real time, an
“intelligent agent”, just like us. On the other
hand, Hal is man made. Thus, we call such an
entity a one with artificial intelligence.
All these capabilities were mostly pure science
fiction. Indeed, back in 1966, two years prior to
the publication of this novel, researchers Bhimani, B., Merrill, R., Mitchell, R., and Stark,
M., suggested that a person sitting at a desk,
by means of a small digitizer and a telephone,
could communicate with a database on a mainframe.
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What is AI?
Roughtly speaking, Artificial Intelligence is intended to understand, and build, intelligent entities.
AI has produced many interesting and important results. But, it used to be difficult.
For example, in the 1960’s, on then a very
powerful IBM 360 mainframe, an analysis of
a sample required 85 seconds for each second
of the voice sample being translated, too slow
to help Hal to communicate with his human
colleagues in real time.
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We have achieved quite a bit....
We have made quite a progress along this line:
speech recognition and synthesis, e.g., the Siri
system equipped with IPhone 4S; logic reasoning and/or planning, e.g., IBM Deep Blue; machine learning, e.g., IBM Watson system; intelligent agents, e.g., automatic vehicle.
For example, in the Third DARPA Grand Challenge took place on November 3, 2007, an autonomous vehicle built by a CMU Racing Team
completed the 55 mile course in an Urban setting, Victorville, California, in about four hours
and won a USD 2M prize.
Let’s have a look....
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Why are we interested in AI?
With AI, we want to study how it is possible
for a brain to perceive, understand, predict,
and then manipulate the world, which is much
larger and complicated than itself.
A much more difficult question is that, if we
understand such a process, how could we build
something with these features?
With its fast speed and big memory, Computers provide an ideal platform for us to test out
our assumptions and realize our dreams.
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Both the newest and the oldest
AI is one of the newest discipline. It was formally initiated in the mid 1950’s. Although it
has accomplished quite a bit, there is still a
long way to go.
On the other hand, the study of intelligence
is also one of the oldest. For 2,000 years,
philosophers have tried to understand how seeing, learning, remembering, and reasoning, could,
as well as should, be done.
The emergence of computers in the early 1950’s
made speculations into a real experimental and
theoretical science.
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Computer and AI
With its huge memory and stunning speed, besides providing a vehicle for creating artificial
intelligence entities, the computer also provides a tool for testing theories of intelligence,
many of which could not stand the test, just
like many of the physics theories.
AI currently consists of many sub-fields. From
such general areas as logic reasoning, to some
very specific ones, such as playing chess.
Many scientists of other areas often move into
AI, where they find the theories and tools that
systemize what they have been doing for a long
time; while AI workers may choose to apply
their methods to any area of human intelligence.
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Various perspectives
There are various definitions of artificial intelligence. Some of them emphasize more on the
thought process and reasoning; while others
emphasize on the behavior.
Another angle is that if it tries to characterize human performance; or some ideal performance, i.e., if it always does the right thing,
or, rationally.
Thus, there could be four approaches, which
have all been followed. A human-centered approach must be an experimental one, involving
assumptions, and experimental confirmations;
while a rationalist approach involves a combination of mathematics and engineering.
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Turing and his Test
Turing (1912-1954) proposed a test to provide
an operational definition of intelligence, when
he defined intelligent behavior as the ability
to achieve human-level performance in all cognitive tasks, sufficient to fool an interrogator. More specifically, a human interrogator
asks questions to, and get answers from, two
sources, one is controlled by a computer, the
other by a human being, without knowing which
is which.
If the interrogator cannot distinguish the sources
based on the answers, then we may say the
compute exhibits sufficiently human intelligence
to pass the Turing test.
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What does it take to pass?
The Loebner Prize, that started in 1990, is an
annual competition that awards prizes to the
Chatterbot considered by the judges to be the
most human-like among the competitors. The
format of the competition is that of a standard
Turing test.
The Loebner Prize Competition in Artificial Intelligence for this year should be held on October 19 at University of Exeter, Exeter, UK.
with the top prize of $4,000 and a bronze
medal.
To pass such a test, a computer would have to
possess such abilities as natural language processing, knowledge representation, automated
reasoning, and machine learning.
Who won the Loebner Test this year?
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Think humanly:
Cognitive modeling
Following this approach, we have to set up
a theory on human being’s thinking first by
studying our own thinking process, or via psychological experiments. Then, we have to express the theory as a computer program. If
the program’s I/O and timing behavior match
with the real thing, we will have some evidence
that some of the program’s mechanisms may
also be operating in humans.
The filed of cognitive science brings together
computer models of AI and experimental techniques of Psychology to construct precise and
testable models of the workings of human mind.
In particular, the GPS (General Problem Solver)
program (1957, Simon and Newell) is to compare its reasoning steps with that of human
subjects solving the same problems.
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Think rationally:
The laws of thought
Aristotle (384-322 BC) was one of the first to
attempt to formalize the thinking process. His
famous syllogisms provides pattern for argument structures that always gave correct conclusions given correct premises. E.g., “Socrates
is a man; all men are mortal; therefore Socrates
is mortal.”
By 1965, programs came to life which, taking a
problem represented in logic notation, is guaranteed to find a solution, if there is one, given
enough space and time. The trick is that, if
no solution exists, we might never know it.
Logic programming is the main tool in this
field.
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Theory and practice
It is not easy to covert informal knowledge into
formal notation (How does a baby recognize
her mother’s face in just a few days?) Also,
there is a big gap between being able to do it
in principle and solve it in practice.
In fact, two essential issues in AI is knowledge
representation and search. The former deals
with representing what we know so that computers also “know”, and the second is how to
let a computer find the useful information to
solve a problem at hand.
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Act rationally:
The rational agent
It is to act to achieve one’s goals, given one’s
beliefs. An agent is just something that perceives and acts. In this approach, AI is regarded as the study and construction of rational agents.
Although making correct inferences is sometimes part of being a rational agent, it is not
always the case, since there might not be any
provably correct things to do; or it is simply an
act of gut feeling, e.g., pulling one’s hand off
a hot stove.
All the cognitive skills listed under Turing Test
are needed to allow rational actions.
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Maybe the real thing?
This approach has two advantages. It is more
general than the “laws of thought” approach
since correct inference is only a useful mechanism, but not necessary.
It is also more amenable to scientific development than human centered approaches, because the concept of rationality is clearly defined and completely general.
The Grand Challenge might be regarded as a
good test of this theory.
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Activities
Choose a topic and write a one-page, single
space, essay.
• What does the character of Hal 9000 represent? Discuss the possible issues and their
implications when human beings are able
to come up with such an intelligent product(s).
• Explore the status quo of artificial intelligence at present. What are among the
most successful accomplishment of modern AI technology?
• What are some of the other influential AI
related characters as described in science
fiction novels?
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• Play with Eliza, do some research about its
history and technology behind it. Why can
Alice talk with you?
• What is the main difference between a robot
and human being?
• If you have watched Spielberg’s “Artificial
Intelligence:AI”, why does David want to
be a real boy? What did he go through?
Compare this David figure with Hal 9000.
• Have you used, or seen a demo, of iRobot,
the carpet cleaner? What kind of intelligence do you think it shows? What kind
of issues will be involved in making a product that will automatically cut your lawn?
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• What is involved in an automatic vehicle?
What issues have to addressed before putting
it on road? Any commercial attempts have
been made? What is the status?
• What do you think about the Turing Test?
Do you think a program really demonstrates
intelligent behavior if it passes the Turing
test? Why or why not?
• Do some investigation of AI application in
your discipline?
• What do you think will happen to AI in the
future?
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