1. Calling a flaw a "feature".
2. The "null hypothesis". (Statisticians' term for the possibility that an observed phenomenon may be due to chance, rather than the conjectured cause.)
3. The idea that if you were in a room falling freely, you could not detect the force of gravity, while if the room were pulled downward faster than free fall, this would seem like negative gravity.
4. The idea of a false "implanted memory". (Long before the "recovered memory" controversy of recent decades, the idea of implanted memories occurred from time to time in science fiction. But what is the earliest example you know of?)
5. A character from a book meets another character who has read about him in the book. Also, characters in the book comment on the literary abilities of a certain writer, who happens to be the author of the book.
6. The suggestion that power transmission poses dangers to human health. (Evidence that exposure to the fields produced by power lines correlated with increased incidence of certain types of cancer was presented by Wertheimer and Leeper in the '80's. So far as I know, that question remains open. But the idea occurred earlier in fiction.)
7. The idea that if one could "replay" some event, the outcome might be different.
8. A story of a useful invention, suppressed by the powers that be because of the loss to them that it would lead to.
9. On whether Pluto should be considered something less than a planet.
10. A novel based on transmigration.
a. The Michelson-Morley Experiment has an interesting parallel in a folk-tale.
b. The words "ascii" and "unicode". Long before 1968, when the "American Standard Code for Information Interchange" was created and abbreviated to ascii, and the more recent development of unicode, those words were in the dictionary.
c. The Russians didn't have to invent a word for "airplane".