The foundations of psychiatry are shaking. As a branch of medicine, it is firmly committed to the existence of mental illnesses, but there is little consensus as to their existence. As a branch of medical science, it presumes to discover the truth about the causes of abnormal human behaviour using scientific methodology, but there is a question mark against the scientific status of psychiatric knowledge. As a science over two thousand years old, one expects some agreement as to the basic form of psychiatric explanation, but instead there is a plethora of conflicting theoretical perspectives or paradigms. In short, as a theoretical enterprise, psychiatry is in a bad way.