The neural organ explains the mind

Abstract

The free energy principle says that organisms act to maintain themselves in their expected states and that they achieve this by minimizing their free energy. This corresponds to the brain’s job of minimizing prediction error, selective sampling of sensory data, optimizing expected precisions, and minimizing complexity of internal models. These in turn map on to perception, action, attention, and model selection, respectively. This means that the free energy principle is extremely ambitious: it aims to explain everything about the mind. The principle is bound to be controversial, and hostage to empirical fortune. It may also be thought preposterous: the theory may seem either too ambitious or too trivial to be taken seriously. This chapter introduces the ideas behind the free energy principle and then proceeds to discuss the charge of preposterousness from the perspective of philosophy of science. It is shown that whereas it is ambitious, controversial and needs further evidence in its favour, it is not preposterous. The argument proceeds by appeal to: (i) the notion of inference to the best explanation, (ii) a comparison with the theory of evolution, (iii) the notion of explaining-away, and (iv) a “biofunctionalist” account of Bayesian processing. The heuristic starting point is the simple idea that the brain is just one among our bodily organs, each of which has an overall function. The outcome is not just a defence of the free energy principle against various challenges but also a deeper anchoring of this theory in philosophy of science, yielding an appreciation of the kind of explanation of the mind it offers.