The Science of the Mind 651 



but which we can remember, may be considered to be stored. 

 Sometimes the contents of this region can be exhumed only by 

 considerable effort, sometimes a very slight stimulus is sufficient. 

 Beneath this layer, again, lies the region of the unconscious, and 

 this region is, normally, quite inaccessible to our conscious mind. 

 The description we have given is, of course, figurative, since we 

 cannot suppose that the mind occupies space. But this division 

 into layers is helpful in enabling us to understand the modern 

 theories of the mind. The unconscious is the seat of the mental 

 elements associated with the great primary instincts, and it is 

 the great source of psychic energy. Of the activities going on in 

 it we have no direct knowledge ; we can infer something, however, 

 as we shall see later, from observation, and more especially, ac- 

 cording to some authorities, from dreams. The unconscious is the 

 very basis of the psychic life of the individual. 



The Importance of Complexes 



Mental phenomena never occur singly, but always in some 

 complex combination or another. It will help us in understand- 

 ing the nature of the mind to consider it as a network of mental 

 elements. Every mental element, every idea as we say, which 

 comes into the conscious mind, calls up others. There are associa- 

 tions of ideas, to use the language of the older psychologists. It is 

 because ideas are associated that we are able to go about our daily 

 lives. If no ideas suggested any others, or if others were sug- 

 gested purely at haphazard, we should never be able even to cross 

 the road. A number of mental elements associated together so 

 as to form some more or less loosely knit system is called a com- 

 plex. To some men, for instance, the sight or sound of a type- 

 writer may always, or usually, suggest to them an office ; the smell 

 of a certain flower may always bring back some early experience, 

 and so on. Associations of this kind associations of ideas, as 

 it were are called complexes. We may think, if we like, of ideas 

 forming groups, and the whole of the contents of the mind as 



