ABSTRACT
Although theoretical, conceptual, and methodological analyses are sometimes alleged to have little relevance for current decisions about public policy, a moment’s reflection makes it obvious that this is by no means necessarily the case. A change in the way in which we conceiveof a public policy problem can clearly have dramatic effects on the policies that are chosen and on the detailed policy research that is proposed. In the early nineteenth century, when “bleeding” was often used as treatment for a variety of diseases, it might have seemed appropriate to do quantitative research on what amount of blood should optimally be drawn from each type of patient in each diagnostic category. Now we would have grave doubts about such suggestions; if the data were poor, or the sample small, or the preconceptions strong, even the quantitative research might fail to show the futility of bleeding. By contrast, apparently rather academic speculation on the spread of various yeasts and other microorganisms led, as we now know, to the “germ theory of disease,” with the most portentous practical consequences.
