Today, many neuroscientists exploring the predictive brain deploy contemporary economics as a similar sort of explanatory heuristic. Scientists have come a long way in understanding how ‘spending metabolic money to build complex brains pays dividends in the search for adaptive success’, remarks the philosopher Andy Clark, in a notable review of the predictive brain. The idea of the predictive brain makes sense because it is profitable, metabolically speaking. Similarly, the psychologist Lisa Feldman Barrett describes the primary role of the predictive brain as managing a ‘body budget’. In this view, she says, ‘your brain is kind of like the financial sector of a company’, predictively allocating resources, spending energy, speculating, and seeking returns on its investments. For Barrett and her colleagues, stress is like a ‘deficit’ or ‘withdrawal’ from the body budget, while depression is bankruptcy. In Blackmore’s day, the brain was made up of sentries and soldiers, whose collective melancholy became the sadness of the human being they inhabited. Today, instead of soldiers, we imagine the brain as composed of predictive statisticians, whose errors become our neuroses. As the neuroscientist Karl Friston said: ‘[I]f the brain is an inference machine, an organ of statistics, then when it goes wrong, it’ll make the same sorts of mistakes a statistician will make.’