organs are only co-operative, and not the exclusive factors in the process of development of the psycho-sexual character, is shown by the fact that, notwithstanding a normal anatomical and physiological state of these organs, a sexual instinct may be developed which is the exact opposite of that characteristic of the sex to which the individual belongs.
In this case, the cause is to be sought only in an anomaly of central conditions,—in an abnormal psycho-sexual constitution. This constitution, as far as its anatomical and functional foundation is concerned, is absolutely unknown. Since, in almost all such cases, the individual subject to the perverse sexual instinct displays a neuropathic predisposition in several directions, and the latter may be brought into relation with hereditary degenerate conditions, this anomaly of psycho-sexual feeling may be called, clinically, a functional sign of degeneration. This perverse sexuality appears spontaneously, without external cause, with the development of sexual life, as an individual manifestation of an abnormal form of the vita sexualis, and then has the force of a congenital phenomenon; or it develops upon a sexuality the beginning of which was normal, as a result of very definite injurious influences, and thus appears as an acquired anomaly. Upon what this enigmatical phenomenon of acquired homo-sexual instinct depends is still inexplicable, and only a matter for hypothesis. Careful examination of the so-called acquired cases makes it probable that the predisposition also present here consists of a latent homo-sexuality, or, at least, bi-sexuality, which, for its manifestation, requires the influence of accidental exciting causes to rouse it from its slumber.
In so-called contrary sexual instinct there are degrees of the phenomenon which quite correspond with the degrees of predisposition of the individuals. Thus, in the milder cases, there is simple hermaphroditism; in more pronounced cases, only homo-sexual feeling and instinct, but limited to the vita sexualis; in still more complete cases, the whole psychical personality, and even the bodily sensations, are transformed to correspond with the sexual perversion; and, in the complete cases, the physical form is correspondingly altered.
