Contributions of epidemiology to psychiatric thought.

As a result of trying to apply both science and humanism to psychological problems, psychiatry is exposed to a welter of confusing issues in which science and intuition are pitted against each other. A growing awareness of the importance of quantification in clinical research and theory construction is having the effect of increasing the polarization. It is suggested in this paper that Karl Jaspers' formulation of ërklaren and verstehen provide a conceptual frame by which orderly relationships can replace much of the confusion and polarization. It is further suggested that this line of thought can be implemented and developed by the use of epidemiologic strategies. Historic and recent examples from the literature are provided in order to illustrate how this can be done.