Airports are diagnostic environments. Under normal conditions, almost everyone behaves the same way — queuing, scanning, walking. The script handles it. You cannot tell who is paying attention. The split appears the moment the script breaks. A flight is cancelled. A gate changes. The system that was supposed to take care of everyone stops working. Watch the reaction. A subset of the crowd freezes. They re-read the same screen four times. They get angry at the staff. They look for someone whose job it is to fix this for them. Their behaviour assumes that the world is supposed to function on autopilot, and that interruption is a category error to be reported to management. A smaller subset starts moving. They reread the gate map. They check three apps. They ask one specific question of one specific person. They reroute. They are not less inconvenienced. They are differently structured. The interruption is not an outrage to them. It is the kind of thing that happens, and the response is to think. This is the simplest field test for the Codex. The script handles the easy moments. Who you are is what you do when the script stops working.