Fantasies are things that can't happen, and science fiction is about things that can happen.
Ray BradburyThe psychiatrist wants to know why I go out and hike around in the forests and watch the birds and collect butterflies. I'll show you my collection some day.Good.They want to know what I do with my time. I tell them that sometimes I just sit and think. But I won't tell them what. I've got them running. And sometimes, I tell them, I like to put my head back, like this, and let the rain fall in my mouth. It tastes just like wine. Have you ever tried it?
Ray BradburySometimes you have intuitive insight about how you think things are going to be, and you write that. Other times you fantasize completely, which has nothing to do with predicting the future.
Ray BradburyYou've got to be able to look at your thoughts on paper and discover what a fool you were.
Ray BradburyScience fiction is any idea that occurs in the head and doesn't exist yet, but soon will, and will change everything for everybody, and nothing will ever be the same again. As soon as you have an idea that changes some small part of the world you are writing science fiction. It is always the art of the possible, never the impossible.
Ray Bradbury