psychiatric diagnosis and psychiatric beliefs. It has been argued by philosophers like Foucault that characterizations of "mental illness" are indeterminate and reflect the hierarchical structures of the societies from which they emerge rather than any precisely defined qualities that distinguish a "healthy" mind from a "sick" one. Furthermore, if a tendency toward self-harm is taken as an elementary symptom of mental illness, then humans, as a species, are arguably insane in that they have tended throughout recorded history to destroy their own environments, to make war with one another, etc. Psychiatric labeling Mental disorders were first included in the sixth revision of the International Classification of Diseases (ICD-6) in 1949. Three years later, the American Psychiatric Association created its own classification system, DSM-I. The definitions of most psychiatric diagnoses consist of combinations of phenomenological criteria, such as symptoms and signs and their course over time. Expert committees combined them in variable ways into categories of mental disorders, defined and redefined them again and again over the last half century. The majority of these diagnostic categories are called disorders and are not validated by biological criteria, as most medical diseases are; although they purport to represent medical diseases and take the form of medical diagnoses. These diagnostic categories are actually embedded in top-down classifications, similar to the early botanic classifications of plants in the 17th and 18th centuries, when experts decided a priori about which classification criterion to use, for instance, whether the shape of leaves or fruiting bodies were the main criterion for classifying plants. Since the era of Kraepelin, psychiatrists have been trying to differentiate mental disorders by using clinical interviews. Experiments admitting "healthy" individuals into psychiatric care In 1972, psychologist David Rosenhan published the Rosenhan experiment, a study questioning the validity of psychiatric diagnoses. The study arranged for eight individuals with no history of psychopathology to attempt admission into psychiatric hospitals. The individuals included a graduate student, psychologists, an artist, a housewife, and two physicians, including one psychiatrist. All eight individuals were admitted with a diagnosis of schizophrenia or bipolar disorder. Psychiatrists then attempted to treat the individuals using psychiatric medication. All eight were discharged within 7 to 52 days. In a later part of the study, psychiatric staff were warned that pseudo-patients might be sent to their institutions, but none were actually sent. Nevertheless, a total of 83 patients out of 193 were believed by at least