計算機器與智能

This should begin with definitions of the meaning of the terms “machine” and “think.” … But this is absurd. Instead of attempting such a definition I shall replace the question by another, which is closely related to it and is expressed in relatively unambiguous words.

The new form of the problem can be described in terms of a game which we call the “imitation game.” It is played with three people, a man (A), a woman (B), and an interrogator (C) who may be of either sex. The interrogator stays in a room apart from the other two. The object of the game for the interrogator is to determine which of the other two is the man and which is the woman.

We now ask the question, “What will happen when a machine takes the part of A in this game?” 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? These questions replace our original, “Can machines think?”

The digital computers considered in the last section may be classified amongst the “discrete-state machines.” These are the machines which move by sudden jumps or clicks from one quite definite state to another.

They can all be done with one digital computer, suitably programmed for each case. It will be seen that as a consequence of this all digital computers are in a sense equivalent.

There are a number of results of mathematical logic which can be used to show that there are limitations to the powers of discrete-state machines. … The short answer to this argument is that although it is established that there are limitations to the powers of any particular machine, it has only been stated, without any sort of proof, that no such limitations apply to the human intellect.

A variant of Lady Lovelace's objection states that a machine can “never do anything really new.” But who can be certain that the “original work” a man has done was not simply the growth of a seed planted in him by teaching, or the effect of following well-known general principles?

Instead of trying to produce a programme to simulate the adult mind, why not rather try to produce one which simulates the child's? If this were then subjected to an appropriate course of education one would obtain the adult brain.

Presumably the child-brain is something like a note-book as one buys it from the stationer's: rather little mechanism, and lots of blank sheets. … Our hope is that there is so little mechanism in the child-brain that something like it can be easily programmed.