MAN --AN ADAPTIVE MECHANISM 



result of the balance struck between these competing 

 stimuli of the two environments. 



The kinetic system, which is strongly driven by the 

 self-preservative stimuli of starvation, of acute or 

 chronic infection, of physical injury or of overwork ; or 

 which is crippled by the deficient functional activity 

 of the brain, thyroid, liver or adrenals, will have a 

 lessened power to respond to the less urgent and more 

 easily deferred stimuli to growth and reproduction. 

 It is known that children grow slowly who suffer from 

 acute and chronic infections, such as oral sepsis, ton- 

 sillitis, adenoids, middle ear infection, caries of the 

 bone and indigestion ; from impure, improper or 

 insufficient food ; from overcrowding, poor ventilation, 

 overwork, cruelty and pain ; from deficient functional 

 activity of the thyroid, hypophysis, liver, brain or heart. 

 It is also known that after the removal of these bur- 

 dens or deficiencies, and the reestablishment of normal 

 internal and external environments, growth is rapid. 

 This is evidenced by the result of feeding thyroid ex- 

 tract to myxcedematous children ; by the rapid growth 

 after the cure of chronic appendicitis, hip joint disease, 

 tonsillitis, adenoids and chronic mastoiditis ; after the 

 substitution of happiness and content for homesick- 

 ness ; and of good hygiene for bad hygiene. Interfer- 

 ence with growth is in direct proportion to the reduction 

 in efficiency of the kinetic system. It does not matter 

 whether this reduction is the result of a decreased effi- 

 ciency of some one link in the system, or of an increased 

 call upon the stored energy for response to contact 

 ceptor, distance ceptor or chemical stimuli, so that less 

 energy is left for other demands. 



