The importance of hostility in affective psychoses has been proven mainly through psychoanalytic investigation. The object of this paper is to determine whether 'well crystallized evidences of hostility are also observable … by ordinary psychiatric measures'.

In their study of fifteen manic-depressive cases, the authors detect hostility and aggressiveness as the outstanding features. In the depressive states the hostility is mainly directed against the patient himself; in the manic state, against the outside world. Although the classical description of the mood of the manic emphasizes the presence of euphoria and elation, it is well recognized that hostility and aggressiveness are equally prominent. The depressive is the slave of a strong and rigid superego, while the superego