We can only see a short distance ahead, but we can see plenty there that needs to be done.

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.

The isolated man does not develop any intellectual power. It is necessary for him to be immersed in an environment of other men, whose techniques he absorbs during the first twenty years of his life. He may then perhaps do a little research of his own and make a very few discoveries which are passed on to other men. From this point of view the search for new techniques must be regarded as carried out by the human community as a whole, rather than by individuals.

I am not very impressed with theological arguments whatever they may be used to support. 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... and hasted not to go down about a whole day' (Joshua x. 13) and 'He laid the foundations of the earth, that it should not move at any time' (Psalm cv. 5) were an adequate refutation of the Copernican theory.

It is possible to invent a single machine which can be used to compute any computable sequence.

La opinión tan generalizada de que los científicos proceden siempre de un hecho bien demostrado a otro hecho bien demostrado, y nunca se dejan influir por una conjetura no probada, es bastante errónea. A condición de que quede bien claro qué son hechos probados y qué son conjeturas, no existe ningún peligro. Las conjeturas son de suma importancia, porque sugieren posibles vías de investigación.

The popular view that scientists proceed inexorably from well-established fact to well-established fact, never being influenced by any unproved conjecture, is quite mistaken. Provided it is made clear which are proved facts and which are conjectures, no harm can result. Conjectures are of great importance since they suggest useful lines of research.

These disturbing phenomena [Extra Sensory Perception] seem to deny all our scientific ideas. How we should like to discredit them! Unfortunately the statistical evidence, at least for telepathy, is overwhelming.