THE ORIGIN OF LANGUAGE 71 



increasing intelligence that has accompanied speech. 

 But we are still unsatisfied, for there are other pos- 

 sibilities of language besides articulate speech. 

 Some tribes of men have a language made almost 

 wholly of gestures, and other animals besides man 

 could certainly have used gestures in developing lan- 

 guage. The answer to our question is, then, not to 

 be found in this simple statement that the human 

 vocal organs made speech possible, and speech then 

 forced the development of mental powers. 



There is at least a partial answer to this question 

 which is to be found along the line of our discussion. 

 Man alone of all animals has discovered the possi- 

 bility of utilizing to its utmost the force of social 

 heredity. Speech, with its accompanying mental 

 growth, is dependent upon this type of inheritance 

 which the lower animals have scarcely utilized at all, 

 and human development has thus been dependent 

 upon the newly acquired, or at least newly empha- 

 sized, power of transmitting acquired characters to 

 one's offspring. But this leads to a second question 

 of equal significance. Why has mankind alone ac- 

 quired the power of utilizing this new factor! The 

 answer which we would give to this question involves 

 all the rest of this work. It may, however, make our 

 discussion clearer if we anticipate the conclusion 

 which we shall be forced to reach. This conclusion is 

 that the force ivJiich has produced the mental de- 

 velopment of man, with all its accompaniments, is the 

 instinct ivhich has resulted in the development of the 

 moral sense. Human evolution and human civiliza- 

 tion have been the result of the exaltation of the eth- 

 ical nature of mankind. 



