442 



PSYCHOLOGY. 



In figures 37 and 38, where the result is ambiguous, 

 we can make the change from one apparent form to 

 the other by imagining strongly in advance the form we 

 wish to see. Similarly in those puzzles where certain lines 

 in a picture form by their combination an object that has 

 no connection with what the picture ostensibly represents ; 

 or indeed in every case where an object is inconspicuous 

 and hard to discern from the background ; we may not be 



Fig. 37. 



Fig. 38. 



able to see it for a long time ; but, having once seen it, we 

 can attend to it again whenever we like, on account of the 

 mental duplicate of it which our imagination noAV bears. In 

 the meaningless French words ^ pas de lieu Rhone que nous,* 

 who can recognize immediately the English ' paddle your 

 own canoe ' ? * But who that has once noticed the identity 

 can fail to have it arrest his attention again ? When watch- 

 ing for the distant clock to strike, our mind is so filled with 

 its image that at every moment we think we hear the longed- 

 for or dreaded sound. So of an awaited footstep. Every 

 stir in the wood is for the hunter his game ; for the fugi- 

 tive his pursuers. Every bonnet in the street is moment- 

 arily taken by the lover to enshroud the head of his idol. 

 The image in the mind is the attention ; the prepercepfioriy 

 as Mr. Lewes calls it, is half of the perception of the looked- 

 for thing. t 



* Similarly in the verses which some one tried to puzzle me with the 

 other day: " Gni n'a bean dit, qm snhot dit, nid a beau dit elk?" 



f I cannot refrain from referring in a note to an additional set of facts 

 instanced by Lotze in his JMedizinische Psychologic, § 431, although I ara 



