CSE 111, Fall 2000

1.  What Is Artificial Intelligence?

       *    What problems are computable?

      then the basic question of artificial intelligence
      (AI) is:

       *    Is "intelligence"/cognition/thinking
            computable?

    (where by "intelligence" I am not necessarily
    referring to whatever it is that is alleged to be
    measured by IQ tests, but simply the kinds of
    mental abilities that cognitive psychologists
    study:  what they call "cognition", and what
    most people call "thinking").

b)    Given our definitions of "computable" and
        "algorithm", the basic question of AI becomes:

        *    Is there an algorithm (or a collection of
             them) that computes (human) cognitive
             processes?

c)    AI is the branch of computer science that
        investigates this question.
 

2.    Other Views on What A.I. Is

        "[AI is] the science of making machines do
        things that would require intelligence if done by
        humans."

    *    Note that this uses humans to tell us how
            to program computers.

b)    According to Margaret Boden, a psychologist,

        "[AI is] the use of computer programs and
        programming techniques to cast light on the
        principles of intelligence in general and
        human thought in particular."

    *    Note that this uses computers to tell us
        something about humans.  (Just as, in other
        sciences, theories are expressed in the
        languages of English, or mathematics, or
        statistics, so, in AI, theories about cognition
        can be expressed in the languages of computer
        programs.)

c)    In fact, AI is both of the above, a 2-way street.
 

3.  A Side-Effect of (2b):

If (human) cognitive processes can be expressed as
    algorithms,
then they are capable of being implemented in
        (non-human) computers.

So:

Are computers executing such algorithms merely
simulating cognitive processes, or are they actually
exhibiting them?

One answer was given by Alan Turing's "Turing Test".
An objection to that answer was given by
    John Searle's "Chinese-Room Argument"
 

4.  The Turing Test

Turing, Alan M. (1950),
``Computing Machinery and Intelligence'',
Mind 59: 433-460.

b)    For a description of the Turing Test, together
        with a description of the Chinese-Room
        Argument, and my own views on them,
        see:

Rapaport, William J. (2000),
"How to Pass a Turing Test: Syntactic Semantics, Natural-Language Understanding, and First-Person Cognition",
Special Issue on Alan Turing and Artificial Intelligence,
Journal of Logic, Language, and Information
9(4): 467-490.

c)    Briefly, the Turing Test considers an interrogator
        and either a human or a computer
        (the interrogator doesn't know which) in a room;
        the interrogator's job is to ask questions of
        whoever or whatever is in the room to see if
        it can be determined whether it's a human or
        a computer.

d)    Turing wrote (in 1950):

        "I believe that at the end of the century
        the use of words and general educated
        opinion will have altered so much that
        one will be able to speak of machines thinking
        without expecting to be contradicted"

        *    Note that it is now (Dec. 6, 2000) the
            "end of the century"!

e)    2 questions:

        *    How would you program a computer to
            pass the Turing test?

        *    What kinds of questions should the
            interrogator ask?
 

5.  An Artificial IQ Test

I have prepared an AIQ test that you might find
interesting.
 

6.  The Chinese-Room Argument

Suppose that the interrogator is a native speaker
of Chinese.

Suppose that there is a human in the other room
who does not understand either spoken or written
Chinese.

Suppose that the human in the room is equipped
with a book that contains an algorithm, written in
English (which the human does understand), that
tells the human how to manipulate certain "squiggles"
(actually, Chinese characters) in certain ways.

Suppose that the interrogator gives to the human
in the room a story in Chinese, followed by a series
of questions about the story, also in Chinese.

Suppose that the human takes this input, which, to
him (I say "him", because in the original version of
the argument, the person in the room is Searle) is
nothing but meaningless squiggles, manipulates the
squiggles according to the algorithm, and outputs
more squiggles.

To the interrogator standing outside the room,
the output consists of perfectly grammatical
and correct answers in Chinese to the questions.

So, from the interrogator's point of view, the man
in the room has passed a Turing test for
understanding Chinese, but from the point of view
of the man in the room, he does not understand
Chinese.

Therefore, the Turing Test fails as a test of
a computer's ability to "understand" or exhibit
real cognition.

I will leave as a final exercise for the reader the
answer to the question whether cognition is
computable.

(For the record, I think it is.  For my reasons,
see my paper on the Turing Test, cited above,
and:

Rapaport, William J. (1998),
"How Minds Can Be Computational Systems",
Journal of Experimental and Theoretical Artificial Intelligence
10: 403-419
 

7.  For More Information on AI, See:

b) SOME STANDARD SOURCES OF INFORMATION ON A.I.