In regard to the clinical and etiological relations between the dream and the psychoses, I will report the following observations as paradigms. Hohnbaum asserts (see Krauss, p. 39), that the first attack of insanity frequently originates in an anxious and terrifying dream, and that the ruling idea has connection with this dream. Sante de Sanctis adduces similar observations in paranoiacs, and declares the dream to be, in some of them, the “vraie cause déterminante de la folie.” The psychosis may come to life all of a sudden with the dream causing and containing the explanation for the mental disturbances, or it may slowly develop through further dreams that have yet to struggle against doubt. In one of de Sanctis’s cases, the affecting dream was accompanied by light hysterical attacks, which in their turn were followed by an anxious, melancholic state. Féré (cited by Tissié) refers to a dream which caused an hysterical paralysis. Here the dream is offered us as an etiology of mental disturbance, though we equally consider the prevailing conditions when we declare that the mental disturbance shows its first manifestation in dream life, that it has its first outbreak in the dream. In other instances the dream life contained the morbid symptoms, or the psychosis was limited to the dream life. Thus Thomayer[70] calls attention to anxiety dreams which must be conceived as equivalent to epileptic attacks. Allison has described nocturnal insanity (cited by Radestock), in which the subjects are apparently perfectly well in the day-time, while hallucinations, fits of frenzy, and the like regularly appear at night. De Sanctis and Tissié report similar observations (paranoiac dream-equivalent in an alcoholic, voices accusing a wife of infidelity). Tissié reports abundant observations from recent times in which actions of a pathological character (based on delusions, obsessive impulses) had their origin in dreams. Guislain describes a case in which sleep was replaced by an intermittent insanity. There is hardly any doubt that along with the psychology of the dream, the physician will one day occupy himself with the psychopathology of the dream. In cases of convalescence from insanity, it is often especially obvious that, while the functions of the day are normal, the dream life may still belong to the psychosis. Gregory is said first to have called attention to such cases (cited by Krauss[39]). Macario (reported by Tissié) gives account of a maniac who, a week after his complete recovery again experienced in dreams the flight of ideas and the passionate impulses of his disease.