Gaupp’s opinion is similar: “In spite of all the methods of modern experimental psychology and of all the more precise and more delicate methods of technique for neurological and psychiatric investigation, there remains a residue, and not an insignificant one, in which we do not arrive at a diagnosis by means of the present exact neurological and psychiatric investigation of the condition at the moment present, but only through its connection with an exact anamnesis and with a laborious exploration of the pathogenesis of the existing condition”. Gaupp accepts even explicitly a Freudian postulation, in that he describes the war neuroses as a flight from psychic conflicts into illness and, alluding to psycho-analysis, he says: “Much preferable is the postulate of the effects of the unconscious on consciousness and the physical system than a psychological theory which seeks by words taken from the sciences of anatomy and physiology to gloss over the fact that the path from the physical to the mental and vice versa is entirely unknown to us”. In another place he goes still further and puts the psycho-analytical postulate of the unconscious in the centre of the whole problem. “If one only admits that mental processes can react upon the body even when they do not lie in the conscious field of vision, then most of the supposed difficulties disappear”. In this connection Hauptmann must also be mentioned. He looks upon the traumatic neuroses as mental illnesses psycho-genetically elaborated and caused through emotional factors, and their symptoms as “unconscious further elaboration of the emotional factors along paths of least resistance”. Bonhoeffer seems to have completely accepted the psychologically complex experiences of psycho-analysis. He holds that the traumatic symptoms are “psycho-neurotic fixations, dissociation phenomena which have been rendered possible through the resultant splitting off of the affect from its ideational content under the influence of the violent emotion”. Birnbaum showed in his excellent summary of the literature of the traumatic neuroses that in many of the explanations of these neuroses (for example, in Strümpell’s theory of covetousness) is summed up a psychogenic wish of hysteria, and says: “If the psychogenic wish, the wish fixation, etc. is an essential component of hysteria then it belongs unconditionally in the definition of the disorder”. Psycho-analysis has long maintained this; as is well known, it regards the neurotic symptoms as expressions of unconscious wishes or as reactions to them.