The facts hitherto expressed concerning the anxiety neurosis already contain some starting points for an insight into the mechanism of this neurosis. In the first place it contains the assumption that we deal with an accumulation of excitement, and then the very important fact that the anxiety underlying the manifestations of the neurosis is not of psychic derivation. Such, for example, would exist if we found as a basis for the anxiety neurosis a justified fright happening once or repeatedly which has since supplied the source of the preparedness for the anxiety neurosis. But this is not the case; a former fright can perhaps cause a hysteria or a traumatic neurosis but never an anxiety neurosis. As the coitus interruptus is rendered so prominent among the causes of anxiety neurosis I have thought at first that the source of the continuous anxiety was perhaps the repeated fear during the sexual act lest the technique will fail and conception follow. But I have found that this state of mind of the man or woman during the coitus interruptus plays no part in the origin of anxiety neurosis, that the women who are really indifferent to the possibilities of conception are just as exposed to the neurosis as those who are trembling at the possibility of it, it all depends on which person suffers the loss of sexual gratification. Another starting point presents itself in the as yet unmentioned observation that in a whole series of cases the anxiety neurosis goes along with the most distinct diminution of the sexual libido or the psychic desire, so that on revealing to the patients that their affliction depends on “insufficient gratification,” they regularly reply that this is impossible as just now their whole desire is extinguished. The indications that we deal with an accumulation of excitement, that the anxiety which probably corresponds to such accumulated excitement is of somatic origin, so that somatic excitement becomes accumulated, and furthermore, that this somatic excitement is of a sexual nature, and that it is accompanied by a decreased psychic participation in the sexual processes—all these indications, I say, favor the expectation that the mechanism of the anxiety neurosis is to be found in the deviation of the somatic sexual excitement from the psychic, and in the abnormal utilization of this excitement occasioned by the former.