To introduce something altogether new would mean to begin all over, to become ignorant again, and to run the old, old risk of failing to learn.

People who think they know everything are a great annoyance to those of us who do.

The saddest aspect of life right now is that science gathers knowledge faster than society gathers wisdom.

When stupidity is considered patriotism, it is unsafe to be intelligent.

So the universe is not quite as you thought it was. You'd better rearrange your beliefs, then. Because you certainly can't rearrange the universe.

In life, unlike chess, the game continues after checkmate.

People think of education as something that they can finish.

There are no nations! There is only humanity. And if we don't come to understand that right soon, there will be no nations, because there will be no humanity.

A robot may not injure a human being, or, through inaction, allow a human being to come to harm.

Violence is the last refuge of the incompetent.

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

It is said that power corrupts, but actually it's more true that power attracts the corruptible. The sane are usually attracted by other things than power.

Think you can and you can do it.Your thoughts are your life.

All grown-ups appear as giants to small children. But Headmasters (and policemen) are the biggest giants of all and acquire a marvellously exaggerated stature.

Every great and deep difficulty bears in itself its own solution. It forces us to change our thinking in order to find it.

We have had a long wait for democracy.

I could have never dreamed what an amazing ride this has been.

Nothing is more powerful for your future than being a gatherer of good ideas and information. That's called doing your homework.

The song of thrush and blackbird, joy that falls so gently on the ears to celebrate another day of life and living, flying free.

Smiling in Heaven isn't required - it's inevitable.

Even prostitutes, alcoholics, embezzlers - I won't rehearse the whole catalogue - need health insurance.