My favorite cult sci-fi and fantasy books you may not have heard of before

I've read 3 out of those 5 books, and I see our preferences differ. For instance, I've a few books from Van Vogt, and I can't imagine I could like anything he wrote.

- "A voyage to Arcturus" tried hard at being strange and philosophical, but it seemed shallow and I did not feel interested.

- "The worm Ouroboros" was better, with a very unusual epic style, both in writing style and in the story. But some points made me cringe, e.g. the focus on nobles and the despise of common people, even heroic characters. Then it got repetitive, with a final trick that felt like a mockery of the whole story.

- "The dying Earth" was a good book, but it is far from my favorites. I prefer continuous novels to collections of short stories, even when they share a common setting. The book sometimes felt like a poetic tale, with nature and nostalgia as strong themes, though it was also quite brutal.

Since anonymous suggestions aren't very useful without any context, I'll match little-known books with famous books:

- If you thought that "1984" had good ideas, but also many stupid parts that spoiled the whole book, then try two older books. "We", by Zamiatin, is a bit old and naive but enjoyable. It was a source of inspiration for "Brave new world" and "1984". The Swede "Kollocain" (1940), by Karin Boye, is excellent, and much more subtle than the latter.

- If you like collections of related short stories, like "The dying Earth", then "The carpet makers" (1995) by Andreas Eschbach is a must. I remember the joy when I finally had a global understanding of the whole situation.

- If you wish for bizarre fantasy, not the epic Tolkien style, not even the dark saga of Ouroboros, but something more gothic and unsettling, then Mervyn Peake's "Titus groans" is perfect.

- I think "Brain twister" (1961) is the only funny book I've read in SF-Fantasy-supernatural.

They're usually the same thing, differing only thematically. Some "hard" sci-fi may be completely grounded in reality, but for most the "sci" is just a background setting. Many space operas are even more fantastical than wizards throwing fireballs at each other. Some fantasy writers go far out of their way to build coherent worlds governed by physical laws just as strict as our own. Both/Either/The genre(s) use the flexibility of an imagined world, whether that's an imagined future or some land of myth, to contrast with the present, and as with the fantastical myths of old, to make moral or political points that couldn't be so easily expressed if weighed down by history and nuance.

Andy Weir does a tight well placed adventure better than most.

I can see that you wouldn't like him if you're more into characters than plot, but that's not what everyone wants.

What's truly infuriating is how awful the tagging on Audible is. "The Lion, the Witch and the Wardrobe" is tagged sci-fi.

They really aren't all that different from each other. One is imaginary things that might one day be possible, and the other is imaginary things that won't ever be possible.

And even then, that can swap between the genres. Scifi often contains FTL tech, which from what we know is almost certainly impossible so it's actually more like fantastical magic. Meanwhile, fantasy can have hard rules for its magic, in which case it acts more like technology that we haven't discovered yet. I haven't read it yet myself, but I've heard of Wizard's Bane, where a programmer is transported to a magical land and becomes really powerful because he treats the magic system like a new programming language.

Other things I've noticed is that scifi tends to involve spaceships and is more mystery oriented, whereas fantasy tends to take place on the ground and is more hero's journey oriented. But even these aren't defining traits. Plenty of scifi books involve investigating alien planets and many contain the hero's journey (including the original Star Wars if you count that as scifi). Meanwhile plenty of fantasy books are on some sort of ship (Narnia - Voyage of the Dawn Treader) and many are more mystery oriented (Harry Potter for example).

Personally, I think a better line of division is hard vs soft. Was the world created first with actual rules and the characters molded to fit the world (Dune, Lord of the Rings)? Or were the characters created first and the rules are bent to create the story that is being desired to tell (Star Trek with its technobabble, Star Wars's prequels and sequels, the entire universe of Harry Potter)?