What are the respective roles of physiological, psychological and social processes in the development of psychiatric disorders? The answer is relevant for deciding on interventions, prevention measures, and for our (self)understanding. Reductionist models assume that only physiological processes are in the end causally relevant. The biopsychosocial (BPS) model, by contrast, assumes that psychological and social processes have their own unique characteristics that cannot be captured by physiological processes and which have their own distinct contributions to the development of psychiatric disorders. Although this is an attractive position, the BPS model suffers from a major flaw: it does not tell us how these biopsychosocial processes can causally interact. If these are processes of such different natures, how then can they causally affect each other? An enactive approach can explain biopsychosocial interaction. Enactivism argues that cognition is an embodied and embedded activity and that living necessarily includes some basic form of cognition, or sense-making. Starting from an enactive view on the interrelations between body, mind, and world, and adopting an organizational rather than a linear notion of causality, we can understand the causality involved in the biopsychosocial processes that may contribute to the development of psychiatric disorders.