There is a renewed interest for complex adaptive system approaches that can account for the inherently complex and dynamic nature of psychopathology. Yet, a theory of psychopathology grounded in the principles of complex adaptive systems is lacking. Here, we present such a theory based on in the notion of adaptive dynamic patterns. We postulate that all observable phenomena of the body and mind are dynamic patterns that emerge from an open complex adaptive system constituted by interdependent biopsychosocial processes located in the individual and its environment, which operate on multiple timescales. Psychopathology is a self-organizing emergent property of a system, meaning that psychopathology arises solely from the interdependencies in the system and is not prescribed by an internal or external ‘blueprint’. While dynamic patterns of psychopathology are highly idiographic in content due to continuous individual-environment transactions, we claim that their change over time can be described by general principles of pattern formation in complex adaptive systems. Our theory thus integrates idiographic and nomothetic science. A discussion of implications for classification, intervention and public health concludes the paper.

We are grateful to Jerillyn Kent for her thorough and thoughtful comments during the editorial process, which have been extremely helpful for improving the final article. We thank Nina de Boer, Olga de Bont, Anna Dapprich and Marieke Glazenburg for their feedback on previous versions of this article. We thank Ralf Cox for producing Figure 1, Jingmeng Cui for co-producing Figure 2, and Nastasia Griffioen for producing Figure 3. The authors report no conflict of interest.

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