Once again, the idea of God leads us to an unresolvable paradox. BTW, in the story, the computer existed in hyperspace. I'd be careful about saying that. Much of the world's most influential literature is, and has always been, fictional. Actually, the most influential literature has always been history, philosophy and scientific texts, none of which are classified as fiction, but yes, fiction can be influential.
Philosophy is a broad subject which can range across both fiction and non-fiction.
Philosophical works which concentrate primarily upon methods of logic and reasoning are clearly non-fiction, while works that focus more upon ideas or morality which cannot be deduced from objective data would seem to fall more in the realm of fiction. Yet, it is those works detailing ideas and morality which have had the most profound influence upon the masses. Indeed, it can. I think you'd also agree that it is based the factual abuses of the institution of slavery. That is the source of its powerful influence.