In the practical handling of a psychiatric problem, one does not treat only for disease entities, such as depression or schizophrenia, but rather for reactions that constitute more or less characteristic samples of what is wrong or not working well. The treatment in the sample or phase escapes being a rule of thumb procedure by a consideration of the likelihood of more far-reaching range involved in the illness, of which the former are only incidents. For example, treatment for insomnia could in most cases be a routine procedure did not the necessity for considering the reaction-set in which it occurs demand certain precautions, impose certain restrictions and offer special light. In the past few years, there have been observed in the Henry Phipps Psychiatric Clinic of the Johns Hopkins Hospital a group of patients with depressive reactions of such character as to demarcate themselves sharply from the general body of