A recent paper by Eiko Fried lists a number of frameworks for understanding mental illness that integrate the biopsychosocial advances in our understanding, one of which (and my own current view) is that of psychological constructs as “complex kinds”:
Conceptualizing psychological concepts through a “complex” approach involves understanding natural processes that co-occur, forming a cluster connected by an underlying causal force. This relationship is probabilistic, not deterministic, and the features of these properties aggregate in imperfect, inconsistent ways. For example, if depression is viewed as a “complex kind,” it would be consistent with the notion that some features of depression are caused by other features, and that different patients may present with various clusters of symptoms. Unlike “natural kinds,” “complex kinds” do not have defined necessary and sufficient features, yet their existence is not purported to be symbolic in the case of “practical” and “social” kinds.