If you don't care about science enough to be interested in it on its own, you shouldn't try to write hard science fiction. You can write like Ray Bradbury and Harlan Ellison as much as you want.

When I sit down to the feast of life ... I'm so busy planning on how to pick up the check, and wondering what the other people think of me for paying it, and wondering if I have enough money in my pocket to pay the bill, that I don't get around to eating.

My old English buddy, John Rackham, wrote and told me what made science fiction different from all other kinds of literature - science fiction is written according to the science fiction method.

I was thinking of writing a little foreword saying that history is, after all, based on people's recollections, which change with time.

I don't think the scientific method and the science fictional method are really analogous. The thing about them is that neither is really practiced very much, at least not consciously. But the fact that they are methodical does relate them.

That's really what SF is all about, you know: the big reality that pervades the real world we live in: the reality of change. Science fiction is the very literature of change. In fact, it is the only such literature we have.

They were two lovely choices. One of them meant giving up every chance of a decent life forever...and the other one scared me out of my mind.