The law of conservation of energy tells us we can't get something for nothing, but we refuse to believe it.

I'm gradually managing to cram my mind more and more full of things. I've got this beautiful mind and it's going to die, and it'll all be gone. And then I say, not in my case. Every idea I've ever had I've written down, and it's all there on paper. And I won't be gone; it'll be there.

Of course there are worlds. Millions of them! Every star you see has worlds, and most of those you don't see.

That's the harm of Close Encounters: that it convinces tens of millions that that's what just science fiction is.

It’s a poor atom blaster that won’t point both ways.

Before another century is done it will be hard for people to imagine a time when humanity was confined to one world, and it will seem to them incredible that there was ever anybody who doubted the value of space and wanted to turn his or her back on the Universe.

It took me thirty-six years; and, in some fifty stories, ranging in length from short-shorts to novels, I think I must have touched, in one way or another, on every aspect of computers and computerization. And (mark this!) I did it without ever knowing anything at all about computers in any real sense. To this day, I don't. I am totally inept with machinery... on my typewriter I turn out books at the contemptible rate of one a month