Schizophrenia research embodies a microcosm of the vexing problems that confront the behavioural sciences, but particularly those disciplines concerned with psychopathology. We are ignorant of the means to prevent schizophrenia because we continue to be ignorant about its aetiology. Despite recognizable descriptions of the syndrome in ancient Hindu treatises (c. 1400 b.c.) and 76 years after its designation as dementia praecox by Kraepelin (1896), we are still grappling with such basic issues as when and how to diagnose Eugen Bleuler's (1911) ‘group of schizophrenias' (cf. Katz, Cole, and Barton, 1968). Despite brilliant advances in molecular biology, neurochemistry, and brain-behaviour phenomena generally, we cannot pinpoint any necessary biological defect in all or most schizophrenics. Despite selfless expenditures of time and energy by gifted psychotherapists and sophisticated social science efforts …