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.

1

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 com-

puter, then travel to the birthplace of

the monolith.”

2

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 up-

set from the harmonics of his voice? Moreover,

now can Hal make the prescription for Dave?

3

“Hal, I am in command of this ship.

I order you to release the manual hiber-

nation 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 inca-

pacitated, the onboard computer must

assume control, unquote. I must, there-

fore, 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 incapac-

itated. Unless you obey my instruc-

tions, I shall be forced to disconnect

you.”

Question: Can Hal tell the “icy” tone of Bow-

man?

“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 confi-

dence 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?

5

“Listen to me very carefully, Hal. Un-

less 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. Nat-

urally, I will follow all your orders. You

now have full manual hibernation con-

trol.”

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 Bhi-

mani, 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 main-

frame.

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What is AI?

Roughtly speaking, Artificial Intelligence is in-

tended to understand, and build, intelligent en-

tities.

AI has produced many interesting and impor-

tant 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 reason-

ing and/or planning, e.g., IBM Deep Blue; ma-

chine learning, e.g., IBM Watson system; in-

telligent agents, e.g., automatic vehicle.

For example, in the Third DARPA Grand Chal-

lenge took place on November 3, 2007, an au-

tonomous vehicle built by a CMU Racing Team

completed the 55 mile course in an Urban set-

ting, 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, Comput-

ers 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 for-

mally 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 see-

ing, 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, be-

sides providing a vehicle for creating artificial

intelligence entities, the computer also pro-

vides 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 intelli-

gence.

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Various perspectives

There are various definitions of artificial intel-

ligence. 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 character-

ize human performance; or some ideal perfor-

mance, 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 ap-

proach must be an experimental one, involving

assumptions, and experimental confirmations;

while a rationalist approach involves a combi-

nation of mathematics and engineering.

13

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 cog-

nitive tasks, sufficient to fool an interroga-

tor. 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.

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 2010 Loebner Prize Competition in Arti-

ficial Intelligence was held on October 23 at

California State University, Los Angeles. with

the top prize of $3,000 and a bronze medal.

To pass such a test, a computer would have to

possess such abilities as natural language pro-

cessing, 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 psy-

chological experiments.

Then, we have to express the theory as a com-

puter program. If the program’s I/O and tim-

ing behavior match with the real thing, we

will have some evidence that some of the pro-

gram’s mechanisms may also be operating in

humans.

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The filed of cognitive science brings together

computer models of AI and experimental tech-

niques of Psychology to construct precise and

testable models of the workings of human mind.

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 argu-

ment structures that always gave correct con-

clusions 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 guar-

anteed 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.

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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 com-

puters 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 per-

ceives and acts. In this approach, AI is re-

garded as the study and construction of ratio-

nal agents.

Although making correct inferences is some-

times 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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This approach has two advantages. It is more

general than the “laws of thought” approach

since correct inference is only a useful mecha-

nism, but not necessary.

It is also more amenable to scientific devel-

opment than human centered approaches, be-

cause the concept of rationality is clearly de-

fined and completely general.

The Grand Challenge might be regarded as a

good test of this theory.

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Philosophical foundation

At around 450 B.C., Aristotle, trying to for-

mulate the laws that governs the rational part

of the mind, developed an informal system of

syllogism for proper reasoning, which in princi-

ple allowed one to mechanically generate con-

clusion, given initial premises. He also noted

intuitive reason.

With at least part of the mind understood, the

next step is to consider the mind as a physical

system. Descartes (1596–1650) told the dif-

ference between mind and matter, as well as

the associated problems.

One problem with a purely physical conception

of the mind is that it leaves little room for free

will. Although Descartes strongly believed the

power of reasoning, he also believed that part

of the mind is exempt from the physical laws.

Thus, the dualism.

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On the other hand, materialist held that all

the world operates according to certain phys-

ical laws. In between there could be an in-

termediate position, in which one accepts that

the mind has a material basis, but denies that

it can be explained by a reduction to ordinary

physical processes.

By and large, philosophy laid a tradition in

which the mind was conceived of as physical

device operating mainly by reasoning with the

knowledge it has.

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The next problem is that where does knowl-

edge come from?

Eventually, Rusell (1872–1970) suggested that

all knowledge can be characterized by logical

theories connected to observation sentences

corresponding to sensory inputs.

Confirmation theorists also tried to understand

the process of acquiring knowledge from expe-

rience.

This is perhaps where Expert System kicks off.

Through knowledge engineering, we get the

knowledge out of an expert, such as how to fix

a car, how to put compatible parts together to

assemble a computer, how to find why some

one is sick, ..., and represent those knowledge

to the computers, so that computer becomes

an expert.

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The last element of philosopher’s perception of

the mind is the connection between knowledge

and action. Particularly, how can an action be

justified?

A typical technique in this regard is the means-

ends analysis as put forward in GPS program

by Newell and Simon around 1970’s. The fol-

lowing argument is fairly common:

I want to get an ’A’ in this course. The

difference between what I have (nothing)

and what I want is one of a number, at

least 92.5.

To reach that goal, I have to do well in

the following areas: homework, projects,

midterm, and final. Thus the ends of

getting of an A justifies my action of

working hard in reading the text books,

staying in programming lab until 2 a.m.,

bugging the professor in his office the

whole time, etc..

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Activities

Choose a topic and write a one-page, single

space, essay.

• What does the character of Hal 9000 repre-

sent? Discuss the possible issues and their

implications when human beings are able

to come up with such an intelligent prod-

uct(s).

• Explore the status quo of artificial intel-

ligence at present. What are among the

most successful accomplishment of mod-

ern 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 intelli-

gence do you think it shows? What kind

of issues will be involved in making a prod-

uct 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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