Good worldbuilding doesn’t come from maps and charts. Those can be used effectively, but they’re always secondary, in my mind, to character reactions. As an occasional writer of the fantastical, I try to ask myself: How do the people inside my fictional world perceive that world? What do they love about it, hate about it, wonder about it?
There’s a great example in Toy Story 2. The Toy Story movies are light on explanation – we never learn how or why toys come alive. But there’s a scene between Woody and Jessie (both toys), where Jessie asks Woody how he feels when his human, Andy, is playing with him. Having once had a human herself, she guesses, wistfully: “Even though you’re not moving…you feel alive. Because that’s how he sees you.” Woody’s response is an astonished “How did you know?”
This is good worldbuilding. The exchange establishes a common experience among toys – that of feeling alive when played with. It’s a sufficiently complex experience; something obvious like “you feel loved” wouldn’t have cut it. Still, it’s familiar. We don’t doubt that sentient toys would feel alive, because we remember how living our toys felt to us in childhood.
True, we still don’t understand how toys work in the Toy Story universe, but we’re privy to how they feel. And that’s enough for us to immerse ourselves in their world.
Worldbuilding isn’t only about explanations. It’s also about experiences.