148 BIOLOGY OF DEATH 



macMne. The broad orderliness and lawfulness of the 

 "whole business of human mortality is impressive. We 

 have seen that different organ systems have well-defined 

 times of breakdown. Or, put in another way, we see that 

 in the human organism, just as in the automobile, the 

 serviceability of the different parts varies greatly. The 

 heart outwears the lungs, the brain outwears both. But 

 we have further, I believe, got an inkling of the funda- 

 mental reason why these things are so. It is broadly 

 speaking, because evolution is a purely mechanistic pro- 

 cess instead of being an intelligent one. All the parts are 

 not perfected by evolution to even an approximately equal 

 degree. It is conceivable that an omnipotent person 

 could have made a much better machine, as a whole, than 

 the human body which evolution has produced, assuming, 

 of course, that he had first learned the trick of making 

 self-regulating and self-reproducing machines, such as 

 living machines are. He would presumably have made an 

 endoderm with as good resisting and wearing qualities 

 as the mesoderm or ectoderm. Evolution by the hap- 

 hazard process of trial and error which we call natural 

 selection, makes each part only just good enough to get 

 by. In the very nature of the process itself it cannot 

 possibly do anything any more constructive than this. 

 The wbrkmanship of evolution, from a mechanical 

 point of view, is extraordinarily like that of the average 

 automobile repair man. If evolution happens to be fur- 

 nished by variation with fine materials, as in the case 

 of the nervous system, it has no objection to using them, 

 but it is equally ready to use the shoddiest of endoderm 

 provided it will hold together just long enough to get 

 the machine by the reproductive period. 



It furthermore seems to me that the results presented 



