IV NOMENCLATURE OF MENTAL OPERATIONS 119 



different ; in fact, the ideas of these impressions 

 become generic. 



If I recollect that a piece of ice was cold yester- 

 day, nothing can strengthen the recollection of 

 that particular fact ; on the contrary, it may grow 

 weaker, in the absence of any record of it. But 

 if I touch ice to-day and again find it cold, the 

 association is repeated, and the memory of it 

 becomes stronger. And by this very simple 

 process of repetition of experience, it has become 

 utterly impossible for us to think of having 

 handled ice without thinking of its coldness. But, 

 that which is, under the one aspect, the strength- 

 ening of a memory, is, under the other, the inten- 

 sification of an expectation. Not only can we not 

 think of having touched ice, without feeling cold, 

 but we cannot think of touching ice, in the future, 

 without expecting to feel cold. An expectation so 

 strong that it cannot be changed, or abolished, 

 may thus be generated out of repeated experiences. 

 And it is important to note that such expecta- 

 tions may be formed quite unconsciously. In my 

 dressing-room, a certain can is usually kept full of 

 water, and I am in the habit of lifting it to pour 

 out water for washing. Sometimes the servant 

 has forgotten to fill it, and then I find that, when 

 I take hold of the handle, the can goes up with a 

 jerk. Long association has, in fact, led me to 

 expect the can to have a considerable weight ; and, 



