596 THE WONDER OF LIFE 



by the premiums which the individuals pay to experience. 



But when we pass from the unicellulars to the multicellu- 

 lars the problem changes. There is a differentiation be- 

 tween body- cells and germ- cells, and although the germ- 

 cells do not live a charmed life within the body it is difficult 

 to suppose that experiences registered in the body can 

 affect the germ- cells in such a specific and representative 

 way that the offspring will profit by the experiences of its 

 parent's body. It is possible that deeply saturating 

 environmental influences may affect both body and repro- 

 ductive organs somewhat similarly. It is possible that 

 very important and frequently recurrent alterations of the 

 ordinary metabolism, which are registered as structural 

 modifications of the body, may sometimes be associated 

 with the formation of characteristic cellular substances 

 which saturate through the body and pass into the germ- 

 cells. Through the germ- cell when it comes to develop, 

 these hypothetical substances may affect the body of the 

 offspring. In point of fact, however, we do not at present 

 know that a structural modification of the body of the 

 parent, impressed from without by some peculiarity of 

 the environment, or brought about through some peculiarity 

 of functioning, can affect the offspring in such a specific 

 or representative way that the parent's modification is 

 transmitted. We do not know that this ever occurs. 



Many thoughtful people find it impossible to believe 

 that somatic experiences do not specifically or representa- 

 tively affect the offspring. How can there be any trading 

 with time worth talking about if the individual gains are 

 not handed on as a legacy to the offspring ? But the 

 confidence with which this question is asked sometimes 

 disappears when we ask another ' And the losses too ? ' 



