The brain’s surprising energy: the free energy principle

Friston has proposed a theory—the free energy principle—that describes with mathematical precision how the brain conserves energy by minimizing surprise.
Things that persist in the world, whether brains, bacteria, or banks, operate within what Friston terms “a circular causality.” These things not only make sense of their worlds, they actively try to influence them for their own survival. This two-way exchange between the inside and the outside is where the free energy principle operates. Simply put, we make sense of the world by either updating our assumptions or by changing the world to make our assumptions true. And both of these arise spontaneously from our drive to make things more predictable.
Contrary to our intuitive experience, the brain is not a passive receiver of stimulus from its environment, but is continuously engaged in an act of interpretation Friston calls active inference. This is a corollary of the free energy principle that explains how we actively forage in the world for evidence that best satisfies our expectations.
As we become familiar with some aspect of the world, all we need is the barest hint of constancy to be satisfied that all is well.
Our quest to minimize surprise is energy efficient, but can lead to the kinds of biases and blunders popularized by Daniel Kahneman in his famous book, Thinking, Fast and Slow.
Active inference is the process through which we build models of our environment that we update with evidence we actively collect. Those familiar with statistics will recognize this description of the brain as particularly Bayesian.
Schizophrenia, which was Friston’s first area of study after medical school, shows the tragic consequences of inference gone wrong. This pathology has taken on a wider cultural meaning in the context of fake news and other forms of social manipulation on the internet.
we store most of our information about the world in the world. So minimizing surprise in the world is mainly a matter of knowing where to look.
We cannot know the external states of the world directly, but only through our senses and our actions (see diagram above). Ultimately it is our internal states—how we feel—that determine how we interpret the evidence of our senses and how we use our bodies to collect more evidence. These three components, our feelings, our perceptions, and our behavior, comprise the Markov blanket that protects us from the causal complexity of the world.
Prolonged uncertainty is a prime cause of workplace stress, which left unchecked can lead to burnout.
The first, and most important, is to choose what to pay attention to.

the interpreter "active inference"

@see "The mind is flat"
@see "No Self, No Problem"