"I'd say their presence is no more relevant to the situation there than would be a copy of 'Die Leiden des jungen Werther' or Heine's 'Romanzero.'"
"I'm sorry I can't agree with you," returned Vance politely. "They are certainly relevant to our investigation, and I had hoped you might be able to explain the connection."
Von Blon appeared to ponder the matter, his face the picture of perplexity.
"I wish I could help you," he said, after several moments. Then he glanced up quickly: a new light had come into his eyes. "Permit me to suggest, sir, that you are laboring under a misapprehension as to the correct scientific connotation of the words in the titles of these two books. I have had occasion to do considerable reading along psychoanalytic lines; and both Freud and Jung use the terms 'Somnambulismus' and 'Dämmerzustände' in an entirely different sense from our common use of the terms 'somnambulism' and 'twilight sleep.' 'Somnambulismus,' in the terminology of psychopathology and abnormal psychology, is employed in connection with ambivalence and dual personality: it designates the actions of the submerged, or subconscious, self in cases of aphasia, amnesia, and the like. It does not refer to one's walking in one's sleep. For instance, in psychic hysteria where one loses one's memory and adopts a new personality, the subject is called a 'Somnambule.' It is the same as what the newspapers commonly refer to as an 'amnesia victim.'"
He rose and went to a bookcase. After a few moments' search he took down several volumes.
"Here we have, for example, an old monograph
