As Mark Miller put it to us, the brain is not a passive receiver of sensory information. It’s constantly generating predictions about what the world should be, and using sensory input only to correct the errors in those predictions. You are not perceiving the world, you are perceiving your brain’s best guess.

The new scientific consensus is that the brain actually “sees” very little. Instead it constructs much of our reality through prediction. The vast majority of what we see and perceive is actually a predictive model.

According to Friston's way of thinking, which he calls active inference, the brain is not the body's helmsman or puppeteer, but its dreamer. Brain and body are bound up in a mutual project to predict the world successfully. Sometimes the brain does the work, sometimes the body.