Psycho-sexually impotent patients are wont to complain that they ‘do not feel’ their penis; others mention marked feelings of coldness in the genital region, while others again speak of the sensation of the penis shrinking up; all these illusions are intensified at the moment of attempted coitus. During the course of the analyses the patients then often say spontaneously that they can ‘feel’ the penis better, that the cold feeling is decreasing, that the penis (unerected) ‘has more consistence’, is ‘more turgid’, etc. For technical reasons it is not advisable to undertake a physical examination on the strength of such complaints; in a few cases, however, I could not evade this, but was unable to confirm the occurrence of any particular ‘coldness’ nor of any anaesthesia nor analgesia, but there certainly was a shrunken-together appearance of the penis. Analytically the unconscious source for these sensations was ascertained to be an infantile castration fear which, as I have detailed elsewhere, 1 is also the origin for that feeling of retraction that many patients get at the root of the penis and in the perineum, especially when afraid of the analyst (father). One of these patients once wakened at night with the sensation that he had ‘no feeling’ of his penis at all; he experienced great anxiety and had to convince himself by touch that he really had a penis. The explanation was as follows: as a child he was threatened with castration for onanistic manipulation of his genitals; whence the ‘dread of touching’ the genitals. The anxious clutching at the penis proved to be a compromise between the wish to masturbate and the dread to be so sorely punished for it. (‘The return of the repressed.’) Those here described and similar paræsthesias often show quite well by their variations the improvements and aggravations in the patient’s condition. Besides unconscious (onanistic) incest phantasies, 2 castration threats are the most frequent causes of psychic impotence; most often it is both (fear of castration on account or the incestuous wish).