Today's science fiction is tomorrow's science fact.

Suppose that we are wise enough to learn and know - and yet not wise enough to control our learning and knowledge, so that we use it to destroy ourselves? Even if that is so, knowledge remains better than ignorance.

To all my gentle readers who have treated me with love for over 30 years, I must say farewell. It has always been my ambition to die in harness with my head face down on a keyboard and my nose caught between two of the keys, but that's not the way it worked out. I have had a long and happy life and I have no complaints about the ending, thereof, and so farewell - farewell.

While he lives, he must think; while he thinks, he must dream.

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

We are reaching the stage where the problems we must solve are going to become insoluble without computers. I do not fear computers, I fear the lack of them.

Life originated in the sea, and about eighty percent of it is still there.