In a field of biology the bibliography of which runs to 500 pages, the need for the formulation of principles might be expected long since to have passed.1 To any one conversant, however, with the endocrine literature, it is obvious that no general agreement on principles— and hence on practice—has yet been reached.
Endocrinology is to an unusual degree an empiric field. Our fundamental conceptions have been attained largely by clinical observations of end-results rather than by rational induction from basic facts determined, after the approved fashion, by controlled experimentation. Empiricism has deserved much of the odium that it carries. That it has a legitimate place in medicine, however, is tacitly conceded by every one who prescribes any medicament the pharmacology of which is not fully known. Indeed, it has often been said that the value of any procedure in medicine must finally be determined empirically in the crucible