i86 ESSAYS OF A BIOLOGIST 



to vary in a remarkable way according as they are 

 being paid in or paid out. We all know to our cost 

 the extraordinary superiority of the epochs when 

 our more elderly relatives were youthful. The fact 

 remains that we are always prone to regard the regis- 

 tering machine as a constant, and to believe that all 

 the variation comes from outside. It is easy to 

 discount the inner variation in ourselves when we are 

 seasick, or in others when they are old and reminiscent, 

 but not only is this discounting sometimes far more 

 difficult, it is sometimes not even attempted. 



What, for instance, are we to say to those who 

 profess to find a harmony in the universe, those to 

 whom poverty and discomfort and hard work appear 

 the merest accidents, to whom even disease, pain, loss, 

 death, and disaster are ' somehow good ' ? You and 

 I would probably retort that we have a rooted dislike 

 to discomfort, that we should most strongly deny that 

 the loss of a friend or even of a leg was anything 

 but bad, that a toothache was not damnably un- 

 pleasant. But I think that if they were philosophic- 

 ally inclined (which they probably would not be), 

 they might justifiably retort that the diff^erence be- 

 tween their universe and ours was due to a difference 

 in their mental machinery, which they had succeeded 

 in adjusting so that it registered in a different and a 

 better way. 



It is at least clear that something of the sort can 

 happen in the intellectual sphere. To the uneducated, 



