Problems in the Definition of 'Mental Disorder'

Current diagnostic manuals in psychiatry such as DSM and ICD offer definitions of mental disorder, though it is recognized that they are unsatisfactory. It is likely that philosophy can help in this problem of definition. I argue that philosophical theories of mind have always implied definitions of mental disorder. Contemporary theories of mind commonly take intentionality to be fundamental, and I consider to what extent mental disorder can be defined in terms of radical failures of intentionality. Dennett has suggested that breakdown of intentional systems is to be explained from the physical stance, but explanations of breakdown from the design stance and even from the intentional stance are possible. Evolutionary theory emphasizes the intentionality of mind and behaviour, and is increasingly applied in models of psychopathology. It is unlikely that these models support the concept of mental disorder at work in current psychiatry.