A lot of popular “genre” fiction is laid out as a puzzle, each with different rules to resolve the puzzle. Mysteries are the most obvious example, but so too are romance, science fiction, and even nonfiction (Malcolm Gladwell is particularly fond of setting up his books and book chapters as puzzles).
Video games, too, are often puzzles, each also falling into particular genres — the platformer, the RTS, the tycoon game. The game engine reinforces the genre by defining what puzzles are possible; the genius of Portal was to discover that the physics engine of the FPS could be used to create new puzzles. But while we’ve seen increasing sophistication and complexity in physics-based puzzles, we’re not seeing quite the same diversity in what I call “social physics engine.”
Not that games are totally lacking in social physics. Fable 2 simply refines the kind of interaction found in Harvest Moon and other “village” games. (Let’s not get into dating games here!). And everyone knows about the best-selling franchise of all time, The Sims. But while making friends and influencing people can be challenging in this genre, there’s nothing all that puzzling about it. Your average pulp romance novel has more suspense built around its “social physics” than these game titles.
I would like to imagine one day having a game built around social dynamics (whether with AI or real people) with the same engaged immersion as Portal succeeded with physics.