I think the new science fiction, which other people apart from myself are now beginning to write, is introverted, possibly pessimistic rather than optimistic, much less certain of its own territory. There's a tremendous confidence that radiates through all modern American science fiction of the period 1930 to 1960; the certainty that science and technology can solve all problems. This is not the dominant form of science fiction now. I think science fiction is becoming something much more speculative, much less convinced about the magic of science and the moral authority of science. There's far more caution on the part of the new writers than there was.

Conversation with George MacBeth on Third Programme (BBC) (1 February 1967), published in The New S.F. (1969), edited by Langdon Jones.