In fact, one good working definition of science fiction may be the literature which, growing with science and technology, evaluates it and relates it meaningfully to the rest of human existence.

Science fiction is the arena of the not-yet, and every science fiction story has this element of not-yet-ness… usually a bit of technology or a scientific discovery that we don’t know about in the real world of the present but that might be a possibility in the future.

Science-fiction balances you on the cliff. Fantasy shoves you off.

If it has horses and swords in it, it’s a fantasy, unless it also has a rocketship in it, in which case it becomes science fiction. The only thing that’ll turn a story with a rocketship in it back into fantasy is the Holy Grail.

Anything you dream is fiction, and anything you accomplish is science, the whole history of mankind is nothing but science fiction.

You don’t have to burn books to destroy a culture. Just get people to stop reading.

What’s wrong with the modern times is that the future isn’t what it used to be.

The only way of discovering the limits of the possible is to venture a little way past them, into the impossible.

Science fiction is, after all, the art of extrapolation.

“But then science is nothing but a series of questions that lead to more questions.”

Fiction is simply dreams written out. Science fiction consists of the hopes and dreams and fears (for some dreams are nightmares) of a technically based society.

Many people have tried to define science fiction. I like to call it the literature of exploration and change. While other genres obsess upon so-called eternal verities, SF deals with the possibility that our children may have different problems. They may, indeed, be different than we have been.