584 PSYCHOLOGY. 



from lack of previous conuectiou between Z and a or c, 

 does not influence a or c. If, for instance, I think of Paris 

 whilst I am hungry, I shall not improbably lind that its 

 restaurants have become the pivot of my thought, etc., etc. 



But in the theoretic as well as in the practical life there 

 are interests of a more acute sort, taking the form of defi- 

 nite images of some achievement, be it action or acquisition, 

 which we desire to effect. The train of ideas arising under 

 the influence of such an interest constitutes usually the 

 thought of the means by which the end shall be attained. 

 If the end by its simple presence does not instantaneously 

 suggest the means, the search for the latter becomes an in- 

 tellectual problem. The solution of problems is the most 

 characteristic and peculiar sort of voluntary thinking. 

 "Where the end thought of is some outward deed or gain, 

 the solution is largely composed of the actual motor pro- 

 cesses, walking, speaking, writing, etc., which lead up to it. 

 Where the end is in the first instance only ideal, as in lay- 

 ing out a place of operations, the steps are purely imagi- 

 nary. In both of these cases the discovery of the means 

 may form a new sort of end, of an entirely peculiar nature, 

 an end, namely, which we intensely desire before we have 

 attained it, but of the nature of which, even whilst most 

 strongly craving it, we liave no distinct imagination what- 

 ever. Such an end is a problem. 



The same state of things occurs whenever we seek to 

 recall something forgotten, or to state the reason for a 

 judgment which we have made intuitively. The desire 

 strains and presses in a direction which it feels to be right 

 but towards a point which it is unable to see. In short, 

 the absence of an item is a determinant of our representa- 

 tions quite as positive as its presence can ever be. The 

 gap becomes no mere void, but what is called an aching 

 void. If we try to explain in terms of brain-action how a 

 thought which only potentially exists can yet be effective, 

 we seem driven to believe that the brain-tract thereof must 

 actually be excited, but only in a minimal and sub-con- 

 scious way Try, for instance, to symbolize what goes on 

 in a man who is racking his brains to remember a thought 

 which occurred to him last week. The associates of the 



