156 ESSAYS OF A BIOLOGIST 



of remembering, and that in any case in most of us 

 a large amount of experience is rendered unconscious 

 by suppression, or an attempt made to force it into 

 the unconscious by repression. He and his followers 

 and other schools of psychologists have pointed out 

 the importance of unresolved conflicts in determin- 

 ing thought and behaviour, and have made it clear 

 that in the ordinary civilized community of to-day a 

 large proportion of those conflicts arise out of diffi- 

 culties connected with the sex-instinct. And, even 

 if we reject the extreme claims made by many Freud- 

 ians, we must admit that psycho-analysis has shown 

 that many cases of actual perversion of instinct may 

 be cured by analytic methods, and that sex occupies 

 a very much larger space in the mind than was pre- 

 viously supposed. It had not been previously sup- 

 posed, because of the fact that it tends to appear in 

 consciousness in disguised form — either sublimated 

 and thus intertwined with other emotions and in- 

 stincts or with unusual objects, or else rationalized 

 as something else, or kept below the surface of con- 

 sciousness as an unfulfilled wish; and because there 

 is a resistance in most of us to recognizing its im- 

 portance. 



This revolution in our thought has proved very 

 unpalatable to many. In just the same way as a 

 large proportion of Darwin's opponents opposed him 

 because they believed that to accept man's simian 

 origin was a repulsive degradation, so many of the 

 opponents of psycho-analysis oppose it because they 



