GENIUS AND MENTAL DISEASE. 667 



wonderfully illustrated in the dagger-scene of "Macbeth." Intent on 

 murder, with "courage screwed to the sticking-place," Macbeth is 

 about to enter the king's chamber, when he is startled and dismayed 

 by an apparition of a bloody dagger in the air. For a moment he 

 questions the reliability of his sight, and exclaims : 



" Is this a dagger which I see before me, 

 The handle towards my hand ? " 



He can not believe the testimony of his eyes, and therefore seeks con- 

 firmation in the sense of touch : 



"... Come, let me clutch thee : 



I have thee not, and jet I see thee still." 



Failing to grasp the dagger, he wonderingly asks : 



" Art thou not, fatal vision, sensible 

 To feeling as to sight ? " 



And then> as if reason were struggling to gain supremacy over the 



senses, he continues : 



"... or art thou but 

 A dagger of the mind, a false creation 

 Proceeding from a heat -oppressed brain ? " 



How suggestive, how replete with truth was this prophetic utterance ; 

 and yet the intensity of his mind's tension — because of the deed to be 

 done and the vision of the instrument for its execution — still makes 

 the terrible idea the dominating factor of his mind, and subordinates 

 the senses to its rule ! He is not yet able to entirely dispel the hallu- 

 cination, and he compares the apparition to the trusted blade at his side : 



" I see thee yet, in form as palpable 

 As this which now I draw. ... I see thee still, 

 And on thy blade and dudgeon gouts of blood 

 "Which ,wa s n °t so before! " 



And then, as if the blood upon the dagger had, by its horrid suggestive- 

 ness, steadied his brain, Reason once more resumes her seat and denies 

 the apparition, by asserting — 



"... There's no such thing ; 

 It is the bloody business which informs 

 Thus to mine eyes." 



These false perceptions, these illusions and hallucinations, while they 

 do not necessarily indicate any mental unsoundness, have been, how- 

 ever, the fruitful source of those apparitions, whether of demons, 

 fairies, or ghosts, which have added to the credulity of man, inten- 

 sified his superstitions, and made possible the organization of human 

 error under such forms of belief as are typically illustrated by witch- 

 craft and spiritualism. 



So long as an individual is conscious that the illusions and hallu- 



