Computing Machinery and Intelligence

A. M. Turing

1. The Imitation Game

  • Can machines think?
  • The imitation game is actually whether a person can distinguish a man from a woman based on written answers alone. One subject tries to fool the judge and the other is truthful.

    • 2. Critique of the New Problem

    It's easier for a machine to imitate a man than vice versa.

    3. The Machines Concerned in the Game

    Only digital computers. (analog computer were more common at the time)

    4. Digital Computers

    An explanation of digital computers.

    5. Universality of Digital Computers

  • Digital computers are discrete state machines.
  • Describes the butterfly effect.
  • Digital computers can mimic any discrete state machine (universal machines)
  • With enough speed and storage, a computer can imitate a person.

    • 6. Contrary Views on the Main Question

  • Turing states that it's meaningless to ask if machines can think.
  • He thinks that in 50 years, definitions of "thinking" will change.

    • (1) The Theological Objection

  • Thinking is a function of man's immortal soul.
  • Can't God give an elephant a soul?
  • Cites Copernican theory against Bible.

    • (2) The "Heads in the Sand" Objection

    Thinking machines are dangerous.

    (3) The Mathematical Objection

    The human mind can encompass infinite states. (no proof)

    (4) The Argument from Consciousness

  • Professor Jefferson's Lister Oration for 1949 (a machine would have to be able to make something; know that it created something; and feel pride).
  • Turing says that if a machine can answer questions about a creation, then it's good enough.

    • (5) Arguments from Various Disabilities

  • No machine can do X.
  • Machines can't make mistakes(?)
  • Machine can't be subjects of their own thoughts

    • (6) Lady Lovelace's Objection

  • The Analytical Engine has no pretensions to originate anything.
  • Machines take me by surprise with great frequency.

    • (7) Argument from Continuity in the Nervous System

  • The nervous system is certainly not a discrete-state machine.
  • it would be very difficult for the interrogator to distinguish the differential analyser from the digital computer.

    • (8) 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. Therefore, we are not machines.
  • we cannot so easily convince ourselves of the absence of complete laws of behaviour as of complete rules of conduct.

    • (9) The Argument from Extrasensory Perception

    the statistical evidence, at least for telepathy, is overwhelming.?! This argument is to my mind quite a strong one.

    7. Learning Machines

  • No convincing arguments
  • Some minds are supercritical. When presented with an idea, may create a theory with secondary, tertiary and more remote ideas.
  • If the mind is like an onion, then it may be mechanical.
  • I should be surprised if more than 109 (bits) was required for satisfactory playing of the imitation game.
  • At my present rate of working I produce about a thousand digits of programme a day, so that about sixty workers, working steadily through the fifty years might accomplish the job, if nothing went into the wastepaper basket.
  • Instead of trying to produce a programme to simulate the adult mind, why not rather try
  • to produce one which simulates the child's?
  • Use reward and punishment to teach a child machine.
  • It is necessary therefore to have some other "unemotional" channels of communication.
  • Alternatively one might have a complete system of logical inference "built in."
  • An important feature of a learning machine is that its teacher will often be very largely ignorant of quite what is going on inside, although he may still be able to some extent to predict his pupil's behavior.
  • It is probably wise to include a random element in a learning machine.
  • Many people think that a very abstract activity, like the playing of chess, would be best. It can also be maintained that it is best to provide the machine with the best sense organs that money can buy, and then teach it to understand and speak English.