128 BIOLOGY AND SOCIAL PROBLEMS 



lectures, I have repeatedly taken occasion to 

 point out their relation to the materials of the 

 body. Organic inheritance is dependent upon 

 the minute amount of these materials in the 

 fertilized egg, perhaps even upon those in the 

 chromosomes. By means of these substances 

 and in no other way are the organically herit- 

 able traits handed on from parent to child. 

 Social inheritance is dependent upon the ap- 

 proximate cubic inch of nervous protoplasm 

 contained in our cerebral cortex and serving 

 as a means for our conscious operations. When 

 this is removed, diseased, or temporarily dis- 

 turbed, as by poisons and the like, the whole 

 personality is shaken to the core or even van- 

 ishes. From a variety of directions, we have 

 as strong reasons for believing that that whole 

 aggregate of nervous states that we recognize 

 as our inmost selves is as essentially associated 

 with the cortical protoplasm as organic inher- 

 itance is with the materials of the egg. In 

 neither case do we understand much of the 

 process. That is a subject for future investi- 

 gation, but research has gone far enough to 

 show that these two classes of operations, the 

 most wonderful, perhaps, that go on in the 

 body, are bound up indissolubly with their 



