I reduce uncertainty
The Briton Karl Friston believes he has decoded how the brain works. Some consider him a genius of the century – others an egoman.
Monday afternoon, Karl Friston's research group meets in an office at University College London. A planned schizophrenia study is discussed. In a dark blue suit, hands clasped in front of his stomach, Friston listens to what his employees are saying. Only an occasional frown reveals that it's working behind half-closed lids. As the discussion dies down, Friston straightens up. He smiles grandfatherly and says, "Now we have to ask ourselves a question: could everything we've believed about the subject be wrong?"
Friston is considered one of the most influential neuroscientists of our time. In recent years, he has caused a sensation with a theory that is supposed to explain literally everything that happens in the brain. The "principle of free energy" (English: "free energy principle"), which Friston first presented a good ten years ago, is based on two basic assumptions. First, the brain is constantly making predictions about the world. Second, it uses the rules of Bayesian statistics. According to Friston, the entire activity of the brain can thus be reduced to a single goal: avoid surprises as much as possible…