Your eyes do not send a live video feed to your brain. Instead, your brain guesses what is out there and uses your senses to check if it is wrong. Illusions happen when the brain locks onto the wrong guess. This means perception is actually our first layer of simulation.

Animals simulate the future

Simulation is not just a human trait. When animals pause before a choice, they are running “trial and error” in their imagination. As primate social groups got larger, they had to simulate something much harder than physical mazes: other minds. They had to start tracking who knows what, who is watching, and who is bluffing.