CLASSIFICATION 57 



Darwin too elaborate to be merely useful ; they possessed a 

 quality in excess of utility, a quality which affects us with 

 a pleasurable emotion, and which we therefore term beauty. 

 Why should not the pea-hen be susceptible to the same 

 emotion ? It might be that the brilliant colouring or bizarre 

 marking of the male was useful to the female at the breed- 

 ing season, because it made her mate more conspicuous, 

 and so diverted the enemy's attention from her, or it made 

 him more terrifying and therefore more useful as her pro- 

 tector, but still in selecting her mate she would choose the 

 one which in her eyes was the more beautiful does not the 

 peacock take endless pains to display his charms? and 

 thus the decorations which were in excess of utility would 

 be perpetuated and still further developed, because the 

 female has this sentiment of beauty which is, as it were, an 

 exaggeration of the sense of utility. Therefore Darwin 

 complicated his theory with the doctrine of Sexual Selec- 

 tion. Control-observations, by eliminating this supposed 

 cause the female's asthetic preference have shown that 

 the doctrine of Natural Selection does not need qualifica- 

 tion. Nature destroys the less fit. In peacocks, fitness is 

 proportional to gorgeousness. 



One more illustration of a control-observation of an 

 entirely different class. When a group of natural phe- 

 nomena are observed, and an explanation of the feature 

 which they present in common is formulated, the theorist 

 asks himself, "Can I find the same result in the absence of 

 any supposed cause ? Can I find the same cause at work 

 without the same result ensuing?" Then he arranges his 

 conditions artificially makes an experiment, that is to say 

 and obtains a certain result. The next step is to omit the 

 condition which he believes to be the cause of the result, 

 and to see if the result is the same. Sometimes, on the 

 other hand, it is not the facts that he needs to test, but his 

 own attitude of mind towards the facts. It is not uncom- 

 mon to hear the remark, even in semi-cultured society, 



