MENTAL AND SOCIAL EVOLUTION 115 



Man is right handed as a rule, while animals are both 

 right and left, for legs, indiscriminately. The two hemis- 

 pheres of the brain function differently. The center of 

 speech, and that of the motor muscles of the right arm, 

 lie in the left hemisphere. The interconnections, be- 

 tween the two centers are close and profuse. Therefore 

 when speech must be emphasized, by pointing to a place 

 indicated in the speech, or in any other manner, it is 

 natural to do it with the right arm or hand, which is 

 stimulated by excitation, near the speech centers. Meyer 

 had said previously, that all babies are left handed, 

 during the first three months of life, and afterwards 

 right handed for the reason of the growing exercise of 

 speech. It may be therefore that the men who are left 

 handed may be found to have been backward in speech 

 when babies, and that the habitual left handedness as 

 babies, continued with these left handed men, until it 

 became a habit through life. It may be that what they 

 did say in early life, needed no emphasizing, by gesture 

 of the hand. 



As to the evolution of what is called altruism, Max 

 Meyer, while he does not consider the question directly, 

 yet he shows that all generalizations and abstractions are 

 impossible without speech, and that speech depends upon 

 the developed nervous system of man. This nervous sys- 

 tem has been evolved with the rest of the body. All 

 human behavior is the direct effect of nervous action, and 

 altruism is one of them a very compound and intricate 

 one. Of course it may be difficult to demonstrate the 

 survival value of pure altruism, as the direct result of 

 natural selection. But it must be treated at least as a 

 secondary effect, growing out of a complex of nerve tissue 

 in the brain, which is the product of natural selection, 

 or survival of the fittest. Altruism would be impossible 



