THE PSYCHOLOGY OF DECEPTION. 149 



the less worth noting. The chests are now opened, and, after hav- 

 ing shown the audience that the second chest comes out of the 

 first, the third out of the second, and so on, he can very readily 

 and quickly draw the last smallest chest from a groove under the 

 table and bring it out as though it had come out of the next larger 

 chest. This is opened and the trick is done. So thoroughly con- 

 vinced is the observer by the correctness of his first three infer- 

 ences that the last box came out of the one before it, that I vent- 

 ure to say this explanation never occurred to one in ten thousand, 

 and that most of the audience would have been willing to affirm 

 on oath that they saw the last box so emerge. The psychology of 

 the process, then, consists in inducing the spectator to draw the 

 natural logical inference, which in this case will be a wrong one. 



The more closely the conditions that lead to correct inferences 

 in ordinary experience are imitated, the more successful will be 

 the illusion ; and one great principle of conjuring illusions is to 

 first actually do that which you afterward wish the audience to 

 believe you have done. Thus, when coins are caught in mid-air 

 and thrown into a hat, a few are really thrown in ; but the others 

 palmed in the hand holding the hat, and allowed to fall in when 

 the other hand makes the appropriate movements. Some of the 

 rings to be mysteriously linked together are given to the audience 

 for examination and found to contain no opening, the audience at 

 once concluding that the rings which the performer retains are 

 precisely like them. In general, to gain the confidence of the per- 

 son to be deceived is the first step alike in sleight of hand and in 

 criminal fraud. 



As we turn from the objective to the subjective conditions of 

 deception, we enter the true domain of psychology ; for the most 

 scientific deceiver is he who emj^loys least external aids, and 

 counts most upon his power of captivating the intellect. Just as 

 we interpret appearances by the forms they most commonly as- 

 sume, so it is our average normal selves that interpret them. A 

 variation in our sense-organs or our judging powers will lead to 

 illusion. The effects of contrast are an apt illustration. Coming 

 from a dark to a light room, the light seems glaringly bright ; a 

 hand immersed in hot water and then in lukewarm water will 

 feel the latter as cold ; when accustomed to the silence of the 

 country the bustle of the city seems unusually noisy, and so on. 

 Fatigue produces similar results. Fatigue the eye for red, and it 

 sees white light as green ; the last mile of a long walk seems the 

 longest ; the last hour of a long wait, the most tedious. So long 

 as we recognize our unusual condition and allow for its effects, we 

 are not deceived ; but under the influence of emotion this power 

 is easily lost. The delusions of the insane are often misinterpre- 

 tations of abnormal sensations under the guidance of a dominant 



