Reformulating the network theory of mental disorders: Folk psychology as a factor, not a fact

Borsboom et al. (2019) argue that the network theory of mental disorders, if correct, blocks the biological reduction of mental disorders. This is mainly argued through a partial reformulation of network theory which combines multiple realizability of symptoms with a realist interpretation of folk psychological explanations. In this article, I argue that (a) the latter is problematic and that (b) the combination of these arguments voids the previous predictive and explanatory power of network theory. I then present a novel way in which network theory could avoid biological reductionism by considering folk psychology not as a fact, but as a structuring cause of causal connections between intentional state symptoms, together with culture and time period. Drawing from this, a novel principle for network theory is proposed, which allows it to retain force against reductionism while also retaining predictive and explanatory power.