Download This will replace the question “Can machines think?”

Artificial Intelligence
A GRADUATE COURSE
WWW.RIBLER.COM
A VISITING PROFESSOR

Randy Ribler
 PhD
from Virginia Tech
 Postdoc at University of Illinois (UIUC)
I was here before in 2006
 I’m absolutely delighted to be back in 2013

LYNCHBURG COLLEGE

Hobbs Hall
CENTRAL VIRGINIA
LYNCHBURG COLLEGE
Small “liberal arts” college
 2000+ students
 50-60 Computer Science Majors
 3 fulltime professors

MY PRIMARY INTERESTS IN AI
Genetic Algorithms
 Rule Induction
 Algorithms for playing games

 Chess
 Chinese
Chess
 Dots and Boxes
WHAT DO YOU WANT OUT OF THIS CLASS?

I would like the class to be project-centered,
but first I need to know:
 Who
are you?
 What do you want to get out of this class?
 What are your career goals?
 What do you already know about AI?
 What subfields of AI are you interested in?
WHAT IS ARTIFICIAL INTELLIGENCE
Do you know a definition?
 Do you have your own criteria?
 Have you heard of the Turing Test?
 What do you think it is?

ALAN M. TURING
Computing Machinery and Intelligence (1950)
- Can machines think?
What are the meanings of the words
“machine” and
“think?”
Today we still have problems defining Artificial Intelligence
What are the meanings of the words
“artificial” and “intelligence?”
COMPUTING MACHINERY AND INTELLIGENCE
(1950)

Imitation Game
 New
“form of the problem,” “Can machines think?”
 Participants
Man
 Woman
 Interrogator (man or woman)

 The
Game
Each participant is in a different room
 Interrogator does not know who is in each room
 Interrogator sends written questions to other participants
 Man tries to convince interrogator that he is the woman
 Woman tries to convince interrogator that she is the woman

TURING TEST

Imitation Game
 Substitute
the man with a machine
“Will the interrogator decide wrongly as often when the
game is played like this as he does when the game is
played between a man and a woman?”
 This
will replace the question “Can machines think?”
SAMPLE QUESTIONS TYPES FROM TURING

Write me a sonnet
 Machine

Perform some mathematics
 Machine

might say its not good at it
might have to appear slow
Solve a chess problems
MACHINE DEFINITION

Digital Computer
 Not
biological clone of a man
 Not necessarily every computer
 Can we imagine a computer that can do well in the
game?
TURING’S PREDICTION

In “fifty years’ time” (year 2000)
 After
5 minutes of interrogation the interrogator will
make the correct identification about 70% of the
time.
TURING’S ANTICIPATED OBJECTIONS

Theological

“God has given an immortal soul to every man and
woman, but not to any other animal or to machines.
Hence no animal or machine can think.”
 Turing

rejects this with an interesting argument
“ In attempting to construct such machines we should not be
irreverently usurping His power of creating souls, any more than we
are in the procreation of children: rather we are, in either case,
instruments of His will providing .mansions for the souls that He
creates.”
 Such
arguments have often been found unsatisfactory in the
past. In the time of Galileo it was argued that the texts, "And
the sun stood still .
TURING’S ANTICIPATED OBJECTIONS

The "Heads in the Sand" Objection
 “The
consequences of machines thinking would be
too dreadful. Let us hope and believe that they
cannot do so."
 “I
do not think that this argument is sufficiently
substantial to require refutation. ”
TURING’S ANTICIPATED OBJECTIONS

The Mathematical Objection
 We
know that some functions are not computable,
so there must be some questions that the
computer will be unable to answer.
 Yes,
but we don’t have any proof that a person can
answer these questions either
 Failing in some areas is not necessarily lack of the ability
to think
TURING’S ANTICIPATED OBJECTIONS


The Argument from Consciousness
"Not until a machine can write a sonnet or compose a
concerto because of thoughts and emotions felt, and
not by the chance fall of symbols, could we agree that
machine equals brain-that is, not only write it but know
that it had written it. No mechanism could feel (and not
merely artificially signal, an easy contrivance) pleasure
at its successes, grief when its valves fuse, be warmed
by flattery, be made miserable by its mistakes, be
charmed by sex, be angry or depressed when it cannot
get what it wants.“ - Jefferson
TURING’S ANTICIPATED OBJECTIONS
We can’t even know these things about a
person? (solipsist point of view)
 We can ask questions as part of the
interrogation that probe understanding

 “In
the first line of your sonnet which reads "Shall I
compare thee to a summer's day," would not "a
spring day" do as well or better?”
TURING’S ANTICIPATED OBJECTIONS

Arguments from Various Disabilities

"I grant you that you can make machines do all the
things you have mentioned but you will never be
able to make one to do X."
X
= Enjoy strawberries and cream
 X = Make mistakes
 Turing
claims most of these objections are
disguised forms of the argument from
consciousness
TURING’S ANTICIPATED OBJECTIONS

Lady Lovelace's Objection - "The Analytical
Engine has no pretensions to
originate anything. It can do whatever we know
how to order it to perform“
 Machines
can change their instructions
 Machines can surprise us – (debugging)
TURING’S ANTICIPATED OBJECTIONS

Argument from Continuity in the Nervous
System - “The nervous system is certainly not a
discrete-state machine. A small error in the
information about the size of a nervous
impulse impinging on a neuron, may make a
large difference to the size of the outgoing
impulse. It may be argued that, this being so,
one cannot expect to be able to mimic the
behaviour of the nervous system with a
discrete-state system.”
TURING’S ANTICIPATED OBJECTIONS

The machine can approximate the continuous
sufficiently to fool the interrogator in
TURING’S ANTICIPATED OBJECTIONS

The Argument from Informality of Behaviour

It is not possible to produce a set of rules purporting to
describe what a man should do in every conceivable set
of circumstances. One might for instance have a rule
that one is to stop when one sees a red traffic light, and
to go if one sees a green one, but what if by some fault
both appear together? One may perhaps decide that it
is safest to stop. But some further difficulty may well
arise from this decision later. To attempt to provide
rules of conduct to cover every eventuality, even those
arising from traffic lights, appears to be impossible.
With all this I agree.
TURING’S ANTICIPATED OBJECTIONS

The Argument from Extrasensory Perception
 Turing
thought that “statistical evidence, at least for
telepathy, is overwhelming”
 Of
course, this has been shown to be incorrect, but it is
interesting to think about.