(7). _Hypochondria_ also causes singular results in the sexual sphere. We have already dealt with the masturbation of certain hypochondriacs, which is often wholly or partly imaginary. Others believe they have committed terrible sexual excesses, when nothing of the kind has occurred. I have seen a hypochondriac married and strongly built, who believed his health was ruined because he cohabited with his wife once every two or three months. Other hypochondriacs become impotent simply because they think they are. Others again imagine they are affected with venereal disease, which they have never contracted. (8). Hysterical men and women have a very peculiar sexuality. Hysteria depends on auto-suggestion or on an exalted and morbid dissociability of psychic activity. A single idea is sufficient in a hysterical subject, to produce the realization of what it represents. The passionate imagination may lead to opinions and actions which are absolutely contradictory. Love and hatred often alternate by transformation. According to the influences to which she is exposed, the same hysterical woman may become a good or evil genius. In the sexual domain the same extremes are produced in a very striking manner. Inflamed by love, a hysterical woman may exhibit phenomenal eroticism and the most violent sexual excesses, while indifference, disgust, or simply distraction by other ideas will render her absolutely frigid. Cold as ice toward other men, she may have insatiable sexual desire for the man she loves. The question is often raised whether a woman can love more than once in her life. There is no doubt that many women are so monogamous by instinct that they cannot love more than once; but it is also certain that a hysterical woman is capable of loving several times, and very different persons at different periods of her life. The personality of certain erotic hysterical women is even so dissociable that they can love with all their strength several men at the same time. But the hysterical woman is also capable of hating a man with as much ardor as she formerly loved him; or, on the contrary, of loving the one she formerly hated, according to the suggestion of the moment. The same phenomena occur in hysterical men.