I've never made a discovery myself, unless by accident. If you write glibly, you fool people. When I first met Asimov, I asked him if he was a professor at Boston University. He said no and … asked me where I got my Ph. D. I said I didn't have one and he looked startled. "You mean you're in the same racket I am," he said, "you just read books by the professors and rewrite them?" That's really what I do.

Quoted in Sally Helgeson, "Every Day", Bookletter, Vol. 3, No. 8 (6 December 1976), p. 8