The voluptuous day-dreamers, not needing material manipulation, may busy themselves with their favorite thoughts while seemingly conversing with their friends or on the most solemn occasions, as when listening to a sermon, etc. These erogenous thoughts, these libidinous images, these constant broodings on sex-matters create a habit which secures such a hold upon the individual that he cannot overcome it. The habit becomes so rooted in some instances that it is impossible for the patients to free their thoughts from fancies and pictures of lustful situations, while alone. Not even with the greatest efforts are they able to rid themselves from imagining erotic scenes of various kinds. Their minds are constantly preoccupied with a single engrossing subject to the exclusion of all other topics and are perpetually turned on sexual subjects, so that they are unable to concentrate their attention upon any other matters. These perennial broodings on sex subjects keep the genital organs in a permanent state of sexual excitation and erethism. While in masturbation the material congestion of the generative organs is removed with each ejaculation, in mental erethism relief by ejaculation is missing. In the first stage of the vicious habit, the morbid mental lubricity and the lascivious unlicensed thoughts may occasionally provoke an ejaculation. But later on, when the genitals have undergone a certain weakness, ejaculation is not brought on any longer by these images, and the genital organs remain in a continual state of material congestion and nervous tension. In this way not only the colliculus and prostratic urethra, as in excesses of copulation and masturbation, but all the genital organs are in a state of chronic inflammation, which in time becomes the cause of impotence.