An informal reconstruction of the free-energy framework, examining the conceptual problems that arise

Recent decades have seen increasing attention given to the free-energy framework. This proposes that many of the phenomena we associate with life, intelligence and adaptation can be explained in terms of a single, mathematical precept: the free-energy principle. This is claimed to apply to the adaptive behavior of primitive organisms as much as it does to the physiological structures of human brains. The proposal is potentially of interest to theorists from multiple disciplines. But as presentations often make intensive use of mathematical notation, it can be hard to understand, even for experts. The present article presents an informal reconstruction, using schematic illustrations. Mathematical notation is largely avoided, while detail and precision are retained as far as possible. The specifically conceptual problems that come to notice in the reconstruction are highlighted and discussed.