274 ELEMENTARY SCIENCE 



There is no insanity among animals, but insanity appears 

 quickly among human beings where self-control is lost. 

 We alone of all living things are responsible for our own 

 acts. It is the price we pay for being at the top of the 

 scale. We can be the happiest of all creatures. We can 

 also be the most miserable. Suicide and crime are un- 

 known except among more highly civilized human beings, 

 and here we would not have them except for failure of the 

 brain to do its work properly; failure to assert itself and 

 be the real master of the body. 



Another thing that increases as brain size increases is 

 the length of time that parents care for the young. Take 

 the fish. Here there is no care for the young at all. There 

 is not even mating. The male discharges sperms in the 

 water just as the female discharges eggs. Fertilization 

 takes place entirely outside the bodies of the parents, 

 and is very uncertain. Eggs and sperms are produced by 

 millions. If they were not, the race of fishes would soon 

 disappear. 



When we come to snakes, however, we find real care 

 of the young; while birds are placed next below mammals 

 for no better reason than the attention they give to the 

 rearing of then: young. It is with human beings, of course, 

 that this matter reaches its extreme form. Human parents 

 are responsible for the protection and care of their children 

 for many years. Of course this means that much fewer 

 young are produced. So the investment of time and 

 money and devotion to each one is greatly increased, and 

 young people represent a very large investment by their 

 parents and by society in general. It is truly a terrible 

 thing not to take this investment seriously and responsibly. 



