Theories are not so much wrong as incomplete

The world of A.D. 2014 will have few routine jobs that cannot be done better by some machine than by any human being. Mankind will therefore have become largely a race of machine tenders.

A robot must protect its own existence as long as such protection does not conflict with the First or Second Laws.

On Earth, we are unmanned by our longing for a pastoral past that never really existed; and that, if it had existed, could never exist again...on the Moon, there is no past to long for or dream about. There is no direction but forward.

Whenever I have endured or accomplished some difficult task -- such as watching television, going out socially or sleeping -- I always look forward to rewarding myself with the small pleasure of getting back to my typewriter and writing something.

Writing is a lonely job. Even if a writer socializes regularly, when he gets down to the real business of his life, it is he and his type writer or word processor. No one else is or can be involved in the matter.

Nonsense! The most hopelessly stupid man is he who is not aware that he is wise.