The Emperor's New Pseudo-Theory: How the Free Energy Principle Ransacked Neuroscience

The Free Energy Principle (FEP) has been hailed as a unifying theory of brain function, behavior, and even biological organization—claiming that all self-organizing systems act to minimize a quantity known as variational free energy. In this paper, we argue that the FEP is not merely flawed but fundamentally unscientific: a theory that evades falsifiability, metabolizes contradiction, and thrives by rebranding tautology as insight. It presents itself as a mechanistic framework while offering no mechanisms, repackages ordinary feedback control as "active inference," and interprets all outcomes—regardless of direction—as evidence in its favor. We demonstrate that its central claims reduce to metaphysical slogans ("systems act to preserve themselves"), its mathematical formalisms obscure rather than clarify, and its explanatory power derives not from predictive success but from rhetorical elasticity. Despite its institutional prestige, the FEP has failed to produce a single novel, testable, and non-retrofit prediction about brain or behavior—while simultaneously crowding out constraint-based, embodied, and falsifiable alternatives. It has become a high-status epistemological sinkhole: a theory that explains everything and, therefore, nothing. We call for its immediate retirement as a scientific framework—and for the restoration of empirical accountability in theoretical neuroscience.