VITAL RESERVES 325 



photo tropism; they are real biological functions. It 

 is popular nowadays to fix attention on those factors 

 in the control of behavior which are imposed on us 

 from outside our own personalities — the hereditary 

 patterns given at birth, pressure of environment, etc. 

 These, too, are real, but they are not the most vital 

 realities in the "continent art of living well." 



The practical problems of making the most and 

 the best of our lives center around the play of those 

 intimate forces that well up inside of us and determine 

 how we are to react to the world in which we must 

 live. Impulse is a crude form of internal control of 

 behavior, very efficient and quite adequate for most 

 of the behavior patterns of lower animals and for the 

 more primitive types of human adjustment. But in a 

 social environment it is inadequate; it breaks down 

 and must be supplemented by rationally appraised 

 purposes and desires and by consciously fabricated 

 ideals. 



These last are just as truly parts of the biological 

 machinery of living on the human plane as are 

 heredity, environment, and physiological impulse. 

 Intelligently directed effort, reinforced by vividly 

 conscious emotional thrills, wishes, hopes, and aspira- 

 tions, are pre-eminently human functions of specif- 

 ically human forms of bodily organization, of which 

 the most distinctive members are in the cerebral 

 cortex. 



Impulse in its elementary biological form is, then, 



