294 NATURE STUDIES. 



state of these faculties" (meaning, apparently, that 

 he overtaxes the faculties, and makes them still more 

 morbid), "and, instead of invigorating, still further 

 debilitates, and often entirely extinguishes his intel- 

 ligence." This caution cannot be too carefully at- 

 tended to. Returning to the analogy between bodily 

 and mental powers, which we touched upon at the 

 outset, we may compare the power of attention to 

 actual muscular strength, as the power of memory 

 may be compared to skill in mastering such and such 

 feats of muscular dexterity, and acquired mental know- 

 ledge to the various athletic exercises which a man 

 has learned to achieve. Now if an athlete finds that 

 his bodily strength is unequal to a task which has 

 hitherto been well within his powers, he would not 

 think (if he were wise) of trying repeatedly to achieve 

 the muscular effort which he has found too much for 

 him. Or (extending the analogy to other ways in 

 which the power of attention may fail) if an athlete 

 finds that he is unable to continue some muscular 

 effort so long as usual, he does not compel Nature to 

 achieve the task which for. the nonce has become too 

 great for him. In either case he perceives that for 

 the time being he is not himself, and by rest or change 

 of some kind (diet, mode of training, or the like), 

 he seeks to restore his powers. At any rate, if he is 

 so unwise, in either case, as to endeavour to master 

 Nature, he increases the mischief, and may entirely 

 lose the powers which had been weakened, and might 

 otherwise have been soon restored, or might at least 



