What Was the Smallville AI Experiment?

Joon Sung Park ran Smallville in 2022 and 2023 to see whether a language model could simulate a whole person, then a whole town.

The models were GPT-3 and then GPT-3.5. They were still rough, but training on the web, Wikipedia, and social media made it possible to pull out human behavior and generate new actions, not only write text or classify a task. Smallville was a game town in the style of Pokemon and The Sims, filled with 25 agents. Each agent had a name, a life story, and an architecture for memory, planning, and reflection. They woke up, went to work, and formed relationships. The simulated day was the day before Valentine's Day. One character organized a party, and others asked each other out. None of that was scripted. It came out of the simulation.

That 2023 experiment introduced simulations of people and a core architecture for agents built on generative models. It was early for agent workflows. The same idea has since been pushed toward simulations that are more accurate, more diverse, and larger.