I called the idea “interoceptive inference”. Just as the brain has no direct access to the causes of exteroceptive sensory signals like vision, which are out there in the world, it also lacks direct access to the causes of interoceptive sensory signals, which lie inside the body. All causes of sensory signals, wherever they are, are forever and always hidden behind a sensory veil. Interoception is therefore also best understood as a process of Bayesian best guessing, just like exteroceptive perception.
