“In this case we have to do with a clever and possibly unscrupulous man who is a specialist in manipulating the human mind. Of course, he practises hypnotic suggestion as a part of his profession--it is the chief agent in modern mental therapeutics. _It is possible_ that by some means he got this young woman into his power after she was dragged from her home. It is possible that he was violently attracted to her, and finding that she did not reciprocate his sentiments, proceeded to subject her individuality to his. How would he do this? He would drug or stun her volition by terror--as, for example, a bird is helplessly fascinated in fear of the snake. Then, using some common mechanical means such as the revolving mirror--staring into her eyes--anything that would fatigue the sensory centres of sight--he would induce a hypnotic trance. In that trance he would suggest to her that her name was no longer Hélène whatever it was--but Fräulein Rosenhagen, that she was a German woman ignorant of French, that she was perfectly happy and contented in his society. In the supernormally receptive state of the hypnotized mind he could give her lessons in German, which would be learned with a speed and accuracy far surpassing that of ordinary education. He would suggest to her that all his lessons persisted after waking. Finally, he would constantly reiterate these suggestions in a succession of hypnotic trances--once the first has been induced, it is easy to bring about the second--until he had reconstructed her personality, or rather imposed a new one upon her consciousness. “There, my dear Vincent, presuming that you are correct in your recognition of this young lady, is a theoretical explanation of the phenomenon which confronts us. For that the young woman genuinely did not recognize you, I am certain.” “She is held in the most diabolical slavery ever conceived, then!” cried Vincent, in despair. “A slavery of the soul! But can nothing be done?” Chassaigne shrugged his shoulders.