You will find men like him in all of the world's religions. They know that we represent reason and science, and, however confident they may be in their beliefs, they fear that we will overthrow their gods. Not necessarily through any deliberate act, but in a subtler fashion. Science can destroy a religion by ignoring it as well as by disproving its tenets. No one ever demonstrated, so far as I am aware, the nonexistance of Zeus or Thor, but they have few followers now.

A precondition for being a science fiction writer other than an interest in the future is that, an interest - at least an understanding of science, not necessarily a science degree but you must have a feeling for the science and its possibilities and its impossibilities, otherwise you're writing fantasy. Now, fantasy is also fine, but there is a distinction, although no one's ever been able to say just where the dividing lines come.

All human plans [are] subject to ruthless revision by Nature, or Fate, or whatever one preferred to call the powers behind the Universe.

I'm quite fond of the writer who told a beginning author, "If you've got a message, use Western Union."

No utopia can ever give satisfaction to everyone, all the time. As their material conditions improve, men raise their sights and become discontented with power and possessions that once would have seemed beyond their wildest dreams. And even when the external world has granted all it can, there still remain the searchings of the mind and the longings of the heart.

Don't mess up the environment until you're quite sure what you're doing.

Many, and some of the most pressing, of our terrestrial problems can be solved only by going into space. Long before it was a vanishing commodity, the wilderness as the preservation of the world was proclaimed by Thoreau. In the new wilderness of the Solar System may lie the future preservation of mankind.