Dune is either produced in human brains or science-fiction.
All imaginative processes are produced in human brains. All science-fiction is from an imaginative process. Either science-fiction or fact.  No facts are proven to be false. Dune is a science-fiction or proven to be false.
∀x (ImaginativeProcess(x) → ProducedInHumanBrains(x))  ∀x (Science-fiction(x) → ImaginativeProcess(x))   ∀x (Science-fiction(x) ∨ Fact(x))  ∀x (Fact(x) → ¬ProvedToBeFalse(x))   Science-fiction(dune) ∨ ProvedToBeFalse(dune)