A mental model is simply a representation of how something works. We use models to retain knowledge and simplify how we understand the world. We can't relearn everything every day, so we construct models to help us chunk patterns and navigate our world more efficiently.

When an audience must work a little harder to understand a piece of art, it builds engagement. It makes characters more believable—real people rarely say exactly what they mean all the time. It can turn what looks to be a simple tale on the surface, such as George Orwell's Animal Farm, into a profound and moving work with lasting impact.

But setting is not just a one-way street, not just the environment acting upon the characters. Characters also act upon and interact with their setting. They navigate its challenges, exploit its opportunities, and leave their mark on its landscape. Every story is a symbiotic relationship between character and setting, a reciprocal exchange of influence and transformation.

A story set in medieval Europe will have different constraints and opportunities than one set in modern-day Tokyo. A character in a small, gossipy village will face different challenges than one in a large, anonymous city. Setting shapes the choices characters make, the conflicts they face, the resolutions they find.