EXPERIMENTAL STUDY OF HEREDITY 567 



ignorance, and crime; and how to increase the number 

 of individuals physically, mentally, and morally more 

 robust and sound; and withal how, if possible, to raise 

 the standard of all desirable human traits. A careful 

 study of heredity and eugenics will make possible a much 

 more intelligent and efficient program for charity work 

 and social betterment. 



488. Investigations Since Mendel. — It must be re- 

 membered that Mendel's most valued contribution was 

 not the observations which he made and recorded con- 

 cerning the garden pea, nor the hypotheses which he ad- 

 vanced on the basis of those observations, but this method 

 of procedure, whereby he elevated the study of heredity 

 to the rank of an exact science. As in the case of all 

 hypotheses, the task for science is to subject them to the 

 most searching tests, to see if they invariably agree with 

 facts, and may be accepted as in all probability embody- 

 ing the actual truth — may be elevated to the rank of 

 theories. The testing of Mendelism has been occupying 

 all the best talents of many investigators since the re- 

 discovery of Mendel's publication, about 1900. Many 

 biologists are still skeptical, others reject the hypotheses, 

 and still others believe they contain the germ of truth, 

 but must be more or less modified. Whether they prove 

 to he erroneous or true is not so important, hut it is impor- 

 tant for us to know which is the case. True or not, 

 they, like nearly all working hypotheses (natural selec- 

 tion, mutation, nebular hypothesis, atomic hypothesis 

 in chemistry, etc.) are rendering, or have rendered, a 

 priceless service to science by pointing the way to further 

 study, which enriches our knowledge of the living world, 

 including ourselves, and therefore increases the intelli- 



