I don’t believe in extraordinary concatenations of coincidence.

Radiation, unlike smoking, drinking, and overeating, gives no pleasure, so the possible victims object.

The young specialist in English Lit, ...lectured me severely on the fact that in every century people have thought they understood the Universe at last, and in every century they were proved to be wrong. It follows that the one thing we can say about our modern "knowledge" is that it is wrong.

In a properly automated and educated world, then, machines may prove to be the true humanizing influence. It may be that machines will do the work that makes life possible and that human beings will do all the other things that make life pleasant and worthwhile

The energy requirements for interstellar travel are so great that it is inconceivable to me that any creatures piloting their ships across the vast depths of space would do so only in order to play games with us over a period of decades. If they want to make contact, they would make contact; if not, they would save their energy and go elsewhere.

The Three Laws of Robotics: 1: A robot may not injure a human being or, through inaction, allow a human being to come to harm; 2: A robot must obey the orders given it by human beings except where such orders would conflict with the First Law; 3: A robot must protect its own existence as long as such protection does not conflict with the First or Second Law; The Zeroth Law: A robot may not harm humanity, or, by inaction, allow humanity to come to harm.

And above all things, never think that you're not good enough yourself. A man should never think that. My belief is that in life people will take you at your own reckoning.