PERSON
Karl Friston
The computational neuroscientist who derived mind from thermodynamics—inventor of the free energy principle and active inference, the theoretical framework that asks not what brains do but what any persistent thing must do, and finds that the answer demands curiosity, action, and a model of the self.
Karl Friston is the physicist of the living. In four decades of work at University College London, he has built a single, densely mathematical framework—the
free energy principle—that begins from the second law of thermodynamics and derives, through variational calculus and Bayesian statistics, an account of perception, action, learning, and curiosity that applies to any system that persists as a distinct thing in a changing world. The argument is as simple in its premise as it is demanding in its execution: to exist separately from the environment, a system must resist the tendency toward disorder—and the only way to do that, Friston argues, is to minimize surprise, to keep the world within the range of states the system expects. Minds are, on this account, prediction machines that act to make the world match their models. But the single most important word in the mature framework is
active: a mind