188 WHAT 18 LIFE 



reactions that result in the maturity of the organism, 

 means a lengthened period of infancy. 



XXV. The theory of the cause of man's erect 

 posture. 



In connection with man's long infancy that is 

 determined by his greater psychic powers, special 

 mention must be made of one of man's outstanding 

 peculiarities — his erect carriage. Utterly helpless as 

 the human baby is for many months, when the little 

 one finally learns to walk he raises himself to the 

 upright position. The normal human walks erect. 



It is my theory that the various peculiarities of 

 any organism, including methods of locomotion and 

 posture, are determined by the dynamics of the 

 system. Man's normal erect carriage, then, is appro- 

 priate to the dynamics of the human organism. The 

 cause of man's normal erect carriage, it would seem, 

 is found in his great brain capacity; that is, man's 

 erect carriage is due to the dynamics of the system 

 that attend the greatness of the Z-system carried by 

 his brain. 



It is meaningless to say, as someone recently said: 

 "A man-like tree-born primate became an earth- 

 borne creature which from sheer necessity ultimately 

 arose to man's estate. This meant the assumption of 

 the erect posture." It is meaningless to say that 

 man has the erect posture because he developed a 

 great toe. 



