The vast majority, who believe in astrology and think that the planets have nothing better to do than form a code that will tell them whether tomorrow is a good day to close a business deal or not, become all the more excited and enthusiastic.

A robot must obey the orders given it by human beings except where such orders would conflict with the First Law. [The Second Law of Robotics]

It is change, continuing change, inevitable change, that is the dominant factor in society today. No sensible decision can be made any longer without taking into account not only the world as it is, but the world as it will be. This, in turn, means that our statesmen, our businessmen, our every man must take on a science fictional way of thinking.

I received the fundamentals of my education in school, but that was not enough. My real education, the superstructure, the details, the true architecture, I got out of the public library. For an impoverished child whose family could not afford to buy books, the library was the open door to wonder and achievement, and I can never be sufficiently grateful that I had the wit to charge through that door and make the most of it.

The great secret of the successful fool is that he's no fool at all

Until now in world's history, whenever we've had a dark age, its been temporary and local. And other parts of the world have been doing fine. And eventually, they help you get out of the dark age. We are now facing a possible dark age which is going to be world-wide and permanent! That's not fun. That's a different thing. But once we have established many worlds, we can do whatever we want as long as we do it one world at a time.

All evil is good become cancerous.