134 Heredity and Social Progress 



goes through the various stages of development 

 from the embryo to maturity, a series of organs 

 appears and then disappears. There is ap- 

 parently no force cutting back the inner nervous 

 structure. After an embryo has gone through 

 the fish stage, the outer organs of the fish dis- 

 appear, but the psychic mechanism that moved 

 these organs may remain. Advanced beings 

 may then have fish thoughts imitation, for ex- 

 ample without any visible fish organs. There 

 are thus many inner processes that have no 

 outer expression, or at least the outer organ is 

 much dwarfed and seldom vitalized with energy. 

 A flow of surplus energy through the brain 

 makes these organs of inner expression active 

 without an effective external expression. The 

 nervous circuit then starts from the brain and 

 brings back an impression apparently from the 

 outside, but which in reality has been caused 

 by the outflow of energy from the brain. Such 

 impressions seem external, although created in 

 the brain. They will modify the person's con- 

 cept of the environment, and consequently his 

 subsequent activity, as much as if they were 

 really objective. Surplus energy can thus ob- 



