Do nothing because it is righteous or praiseworthy or noble to do so; do nothing because it seems good to do so; do only that which you must do and which you cannot do in any other way.
Ursula K. Le GuinScience fiction - and the correct shortcut is 'sf' - uses actual scientific facts or theories for the source ideas or framework of the story. It has some scientific content, however speculative. If it breaks a law of physics, it knows it's doing so and follows up the consequences. If it invents a society of aliens, it does so with some respect for and knowledge of the social sciences and what you might call social probabilities. And some of it is literarily self-aware enough to treat its metaphors as metaphors.
Ursula K. Le Guin