240 SYSTEMS OF TREATING STAMMERING and repelling the dentist. As an example of "con- version" he cites the fact that the recollection of an unavenged wrong may give rise to invective language. These "hysterical symptoms" are "determined" by the nature of the "psychic traumata." And the "psychic trauma," according to Freud, is a "re- pressed" wish: "What were those forces, and what were the conditions of this repression, in which we were now able to recognize the pathogenic mechanism of hysteria? A comparative study of the pathogenic situations, which the cathartic [or psycho- analytic] treatment has made possible, allows us to answer this question. In all those experiences, it had happened that a wish had been aroused, which was in sharp opposition to the other desires of the individual, and was not capable of being reconciled with the ethical, aesthetic and personal pretensions of the patient's personality. There had been a short conflict, and the end of this inner struggle was the repression of the idea which presented itself to consciousness as the bearer of this irreconcilable wish. This was, then, repressed from con- sciousness and forgotten. The incompatibility of the idea in question with the 'ego' of the patient was the motive of the re- pression, the ethical and other pretensions of the individual were the repressing forces. The presence of the incompatible wish, or the duration of the conflict, had given rise to a high degree of mental pain; this pain was avoided by the repression. This latter process is evidently in such a case a device for the protection of the personality."1 1 Freud, "Lectures and Addresses on Psychology and Pedagogy at Clark University," p. 13.