"[Responding to the perceived surrealism of Clangers] They're surreal but logical. I have a strong prejudice against fantasy for its own sake. Once one gets to a point beyond where cause and effect mean anything at all, then science fiction becomes science nonsense. Everything that happened was strictly logical according to the laws of physics which happened to apply in that part of the world."
January 1, 1970
https://en.wikiquote.org/wiki/Oliver_Postgate