472 SUMMARY AND CONCLUSION. 



inherent in the very size and remoteness of his problems, that is absent in the 

 brief laboratory experiments that have taken place under the eye of man. His 

 problems must be viewed from a great distance, but one that gives a large per- 

 spective, and draws a vast range of structural changes into a single horizon where 

 sporadic details disappear, and only those events catch the eye that are massed 

 around some central cause or are ranged with monotonous regularity along some 

 common line of physiological upheaval. 



In so far as we may judge from the teachings of morphology, the perfection 

 of physical organization is reached in man. The structural differences between 

 him and the higher mammals are insignificant; but the potential differences 

 created by his upright gait, his use of the hand as a tool, his power to make 

 his experience the property of another, to look into the past at what occurred 

 before his existence, and to predict what will occur when he has ceased to exist, 

 are faculties of great creative power, which in a true biological sense constitute 

 the supreme crisis of organic evolution, and mark the advent of man as the 

 beginning of a new class of animals. 



Organic evolution is progressive differential growth, in more intricate, ever 

 narrowing environments. It is primarily concerned with obtaining, preparing, 

 and distributing the raw materials of life; in perfecting the coordinate action of 

 the great bodily functions; and in establishing more economic biologic and cosmic 

 relations. In man, growth and the internal organic adjustments to the above 

 indicated ends have reached their optimum level, and progress in that direction 

 has practically ceased. Further progress must be in the extension of man's con- 

 tact with, and control over nature by the creation of instruments of power and 

 precision; in the development of his intellectual, artistic and sympathetic facul- 

 ties; in perfecting the social organization of humanity, and in the creation of social 

 consciousness. 



