The free-energy principle (FEP) is a formal model of neuronal processes that is widely recognised in neuroscience as a unifying theory of the brain and biobehaviour. More recently, however, it has been extended beyond the brain to explain the dynamics of living systems, and their unique capacity to avoid decay. The aim of this review is to synthesise these advances with a meta-theoretical ontology of biological systems called variational neuroethology, which integrates the FEP with Tinbergen's four research questions to explain biological systems across spatial and temporal scales. We exemplify this framework by applying it to Homo sapiens, before translating variational neuroethology into a systematic research heuristic that supplies the biological, cognitive, and social sciences with a computationally tractable guide to discovery.

自由能原理（FEP）是神经元过程的正式模型，在神经科学中被广泛认为是大脑和生物行为的统一理论。然而，最近它已经扩展到大脑之外，可以解释生命系统的动力学及其避免腐烂的独特能力。本综述的目的是将这些进展与称为变异神经行为学的生物系统元理论本体论综合起来，该本体论将 FEP 与廷伯根的四个研究问题相结合，以解释跨空间和时间尺度的生物系统。我们通过将这一框架应用于智人来举例说明，然后将变分神经行为学转化为系统的研究启发式方法，为生物、认知和社会科学提供计算上易于处理的发现指南。