Build a Real Universal Turing Machine - PowerPoint PPT Presentation

1 / 21
About This Presentation
Title:

Build a Real Universal Turing Machine

Description:

Developed alpha-beta tree idea. Made his program learn to improve itself ... Pattern recognition. AI Developments from 1956 - 1963. Herbert Simon, 1957 ' ... – PowerPoint PPT presentation

Number of Views:116
Avg rating:3.0/5.0
Slides: 22
Provided by: csdAb
Category:

less

Transcript and Presenter's Notes

Title: Build a Real Universal Turing Machine


1
Build a Real Universal Turing Machine
  • By now had all necessary ideas 1946 Turings
    plans got approval
  • Automatic Computing Engine (ACE)
  • Progress was slow lack of cooperation
  • Turing without influence, disillusioned
  • (full ACE was not actually complete until 1957
    (obsolete))
  • 1947 Turing back to Cambridge
  • Interest in Neurology
  • Wrote early paper on Neural Nets
  • Believed complex mechanical system could exhibit
    learning ability
  • 1948 Turing and Champernowne wrote a chess
    program
  • (for a computer that did not yet exist.)
  • 1948 Manchester Computer completed
  • Turing accepted post as deputy director
  • Worked on software for Manchester Mark I
  • 1950 Computing Machinery and Intelligence
    published
  • but became more interested in biology -
    morphogenesis

2
Alan Turing
The 'skin of an onion' analogy is also helpful.
In considering the functions of the mind or the
brain we find certain operations which we can
explain in purely mechanical terms. This we say
does not correspond to the real mind it is a
sort of skin which we must strip off if we are to
find the real mind. But then in what remains we
find a further skin to be stripped off, and so
on. Proceeding in this way do we ever come to
the 'real' mind, or do we eventually come to the
skin which has nothing in it? In the latter case
the whole mind is mechanical.
3
Turings End
  • March 1952 Arrested for Gross Indecency
  • No denial - Saw no wrong with his actions
  • Convicted given choice
  • Prison
  • Oestrogen injections
  • Lost security clearance for GCHQ
  • June 1954
  • Why apple?
  • Conspiracy theories
  • Security risk
  • Recognition Turing Award established (ACM, 1966)

4
1956 Dartmouth Conference The Founding Fathers
of AI
Alan Newell
Herbert Simon
Arthur Samuel
And three others Oliver Selfridge (Pandemonium
theory) Nathaniel Rochester (IBM, designed
701) Trenchard More (Natural Deduction)
5
Dartmouth Conference The Founding Fathers of AI
  • First degree in mathematics
  • Graduate work on finite automata
  • Got interested in digital computers after Summer
    working at IBM
  • Was teaching at Dartmouth
  • Brought together the researchers
  • Labelled the field Artificial Intelligence
  • Later
  • Worked on Formal Logic side of AI
  • Invented LISP programming language
  • Won Turing Award in 1971

6
Dartmouth Conference The Founding Fathers of AI
  • 1951 built a neural net out of vacuum tubes,to
    train a simulated rat to get out of a maze
  • Combined learning with planning ahead in his
    Ph.D. thesis
  • Later
  • Society of Mind idea
  • Work on artificial neural networks proved
    perceptrons cant solve some problems
  • Work in theoretical Computer Science
    2-pushdown-stack automaton Turing Machine
  • Won Turing Award in 1969
  • Recent book The Emotion Machine

7
Dartmouth Conference The Founding Fathers of AI
  • Most famous of all participants,
  • but not for AI.
  • Worked on analogue computer with cogs and wheels
  • Showed that electromechanical relay switches
    could solve boolean algebra problems
  • digital instead of analogue
  • Lead to digital calculators
  • 1948 A Mathematical Theory of Communication
  • 1950 created mechanical mouse
  • Could find its way out of a maze
  • Learnt from experience
  • 1950 wrote about chess playing computer program
  • Made a fortune in Las Vegas applying his maths to
    roulette etc.

8
Dartmouth Conference The Founding Fathers of AI
  • Algorithmic Probability
  • probability of some string having been generated
    by an algorithm
  • Applied to Induction
  • Optimal Machine Learner
  • Theoretical idea
  • Not computable
  • But can be approximated

9
Dartmouth Conference The Founding Fathers of AI
  • Originally a political scientist how
    bureaucracies function
  • Became interested in organisational decision
    making
  • Around 1954 he decided best way to study
    problem-solving is to simulate on computer
  • Developed experimental technique of verbal
    protocol analysis
  • Interested in role of knowledge in expertise
  • 1978 won Nobel Prize in Economics

Herbert Simon
Over Christmas, Allen Newell and I created a
thinking machine.January 1956
10
Dartmouth Conference The Founding Fathers of AI
Alan Newell
  • 1955 designed a chess playing program
  • Later
  • 1983 Developed SOAR architecture
  • Attempting a unified theory of cognition

11
Dartmouth Conference The Founding Fathers of AI
  • 1956 Logic Theory Machine
  • Saw that theorem proving can be reduced to search
  • Search tree to find a proof for a theorem
  • Considered to be first AI program
  • 1957 General Problem Solver
  • Heuristics
  • Means-ends analysis
  • 1975 won Turing Award

Alan Newell
Herbert Simon
12
Dartmouth Conference The Founding Fathers of AI
  • Developed a checkers playing program
  • Developed alpha-beta tree idea
  • Made his program learn to improve itself
  • 1962 his program beat a state champion

Arthur Samuel
13
McCarthy et al 1955
We propose that a 2 month, 10 man study of
artificial intelligence be carried out during the
summer of 1956 at Dartmouth College in Hanover,
New Hampshire. The study is to proceed on the
basis of the conjecture that every aspect of
learning or any other feature of intelligence can
in principle be so precisely described that a
machine can be made to simulate it. An attempt
will be made to find how to make machines use
language, form abstractions and concepts, solve
kinds of problems now reserved for humans, and
improve themselves. We think that a significant
advance can be made in one or more of these
problems if a carefully selected group of
scientists work on it together for a summer.
14
1956 Dartmouth Conference What was achieved?
  • Not much
  • People didnt agree on the format and werent all
    there together
  • Newell and Simon didnt spend much time
  • Too busy working on their logic theorist
  • McCarthy was disappointed
  • But got people to know each other

15
Main Thrusts of Work in Early Days
AI Developments from 1956 - 1963
  • Reduce the search tree for search programs
  • For example, search programs for
  • Logic Theorems
  • Geometry theorems
  • Algebra
  • Make computers learn for themselves
  • For example
  • Chess playing machines
  • Checkers playing machines
  • Pattern recognition

16
Herbert Simon, 1957
It is not my aim to surprise or shock you but
the simplest way I can summarize is to say that
there are now in the world machines that can
think, that can learn and that can create.
Moreover, their ability to do these things is
going to increase rapidly until in a visible
future the range of problems they can handle
will be coextensive with the range to which the
human mind has been applied.
17
Newell and Simons progress
  • Discovered that humans dont really act like
    Logic Theorist
  • Psychologists Moore and Anderson had pioneered
    think aloud experiments
  • Other AI researchers were merely concerned with
    programs that performed well
  • Newell and Simon wanted programs that solved
    problems in the same ways as humans
  • They branched off
  • More Cognitive Science than core AI
  • Developed the general problem solver (GPS)
  • Using heuristics
  • Using means-end analysis
  • Solved monkey-chair-banana type problems

18
Work at IBM
  • Minsky hired Herbert Gelernter to work on new IBM
    704
  • Geometry Theorem Prover
  • Gave visual input of geometry problem by coding
    it in (not camera)
  • This input reduced branching factor from 1000 to
    5
  • Took Gelernter 3 yrs to program it (much longer
    than expected)
  • Also at IBM
  • Samuel working on his checkers program
  • Alex Bernstein working on chess program

19
Trouble at IBM
  • AI work noticed by popular press
  • Publicity attracted attention of IBM shareholders
  • Asked T. J. Watson (president of IBM)
  • explain why research dollars were being used for
    "frivolous matters"
  • IBM noticed that customers were frightened of
    idea of "electronic brains" and "thinking
    machines
  • 1960 Internal report prepared recommended IBM
    stop AI
  • IBM told customers
  • computers will only do what they were told
  • Bernstein became psychiatrist
  • Gelernter became physicist
  • Samuel went to Europe

20
McCarthys progress
  • Developed LISP programming language
  • List Processing
  • Makes it easy to program AI ideas
  • Makes it easy for a program to alter its own
    instructions
  • McCarthy wanted programs to add to their own
    commonsense
  • To deduce consequences
  • Started looking at IF-THEN rules (like later
    expert systems)
  • LISP was heavy on computer power more useful in
    1970s
  • McCarthy also pioneered idea of time-sharing
    computers

21
Minskys progress at MIT
  • Sputnik left US behind technologically
  • US created DARPA
  • 1963 MIT got over 2M for Machine Aided Cognition
  • MAC project brought MIT about 3M a year in
    grants thereafter
  • Minskys student James Slagle worked on SAINT
    program
  • Solved symbolic integration problems
  • Later evolved into MACSYMA
Write a Comment
User Comments (0)
About PowerShow.com