DEGENERACY — TREDGOLD. 549 



variations may be divided into two main groups: Firstly, those 

 which connote an increased potentiality for development in some 

 particular direction, thereby placing the individual at a greater 

 advantage in the struggle for existence. These may be termed 

 " progressive " variations, and they obviously lie at the root of 

 progressive racial evolution. Secondly, those which connote a dimin- 

 ished potentiality for development of such a nature as to impair the 

 survival value. These may be termed " retrogressive " variations and 

 lie at the root of social degeneracy. It is with this latter class only 

 that we are now concerned. 



The prevention of the perpetuation of these retrogressive varia- 

 tions is clearly a social problem of great moment, and comprises 

 what is known as restrictive or negative eugenics. But the prob- 

 lem of their causation is even more important; for restrictive 

 eugenics, however complete, can never prove entirely satisfactory 

 so long as degenerates are still being produced de novo. Accord- 

 ingly it is chiefly with the question of causation that it is proposed 

 to deal. 



There are three chief views as to this causation, which may be dis- 

 cussed seriatim. The first is, that degeneracy is not the expression 

 of any new germinal change, but the perpetuation of a defect which 

 has existed in certain strains or stocks of the human race from the 

 very beginning or from a Simian ancestry. This idea has probably 

 occurred to most thinkers on the subject, but it has recently again 

 been advanced by Dr. C. B. Davenport, of America. Doctor Daven- 

 port, 1 speaking of the origin of mental defect, says : 



The conclusion is forced upon us that the defects of this germ plasm have 

 surely come all the way down from man's apelike ancestors, through 200 

 generations or more. The germ plasm that we are tracing remains rela- 

 tively simple ; it has never gained, or only temporarily at most, the one or 

 the many characteristics whose absence we call (quite inadequately) "de- 

 fects." Feeble-mindedness is thus an uninterrupted transmission fron? our ani- 

 mal ancestry. It is not reversion ; it is direct inheritance. 



Now, with regard to this theory, we must either assume that the 

 defect has been present since the very origin of life, or that it has 

 appeared at some subsequent period. On the former view it is 

 presumed that the innate potentiality only sufficed for the attain- 

 ment of a certain low stage of mental development; degeneracy, 

 however, is no mere evolutionary arrest at some particular phase; 

 it is usually seen as, if I may venture to use such a term, a pro- 

 gressive retrogression of certain stocks. If, however,' we admit 

 that the variation has made its appearance at some later stage of 

 evolution, then this theory affords no explanation as to its causation; 



1 " The origin and control of mental defectiveness," 1912. 

 i:366r ( 0°— 20 -36 



