272 FOOT-NOTES TO EVOLUTION. 
tendencies and irrelevant impulses left us by our ances- 
tors. The child is a mixture of imperfectly related 
impulses and powers. It is a mosaic of 
ancestral heredity. Its growth into per- 
sonality is the process of bringing these 
elements into relation to each other. 
In his study of the phenomena of “conversion,” 
Edwin Diller Starbuck gives this view of the physio- 
logical phenomena associated with the 
development of personality, the build- 
ing up of a se/f by a process which 
“is primarily unselfing.” “It is pretty well known,” 
Dr. Starbuck says, “that the quality of mind is much 
dependent upon the fineness of nervous structure. The 
child has about as many nerve cells as the adult. They 
differ from those of the adult in form. Those of the 
child are mostly round, whereas those of the adult have 
often very many branches with which they connect with 
the other cells. Nervous growth seems to consist large- 
ly in the formation of new nervous connections. The 
rapid growth at puberty probably means that at that 
time there is a great increase in nervous branching. 
The increased ramification of nervous tissue probably 
determines the ability for seeing in general terms, for 
intellectual grasp, and for spiritual insight. The rapid 
formation of new nerve connections in early adolescence 
may be the cause of the physiological unrest and men- 
tal distress that intensifies into what we have called the 
sense of incompleteness which precedes conversion. 
The mind becomes a ferment of half-formed ideas, as 
the brain is a mesh of poorly organized parts. This 
creates uncertainty, unhappiness, dejection, and the like, 
because there is not the power of free mental activity. 
The person is restless to be born into a larger world 
that is dimly felt. Finally, through wholesome sugges- 
Development 
of the ego, 
The building 
of the self. 
