RELATION OF GENES TO CHARACTERISTICS 203 



nature, has small chance of escaping that fate. But with 

 the two-egg twins, made up of diverse original materials, 

 the situation was different. Their environments were as 

 similar as were those of the one-egg twins. But of the 17 

 pairs of this kind, in only three cases was the other mem- 

 ber of the pair found to have a criminal record. In the other 

 14 pairs the fate of the two was quite diverse. One was a 

 criminal in each case; the other was not. 



Thus it is clear that everything that helps to determine 

 whether a man shall be a criminal or a good citizen is deeply 

 affected by the materials of which the individual is made, 

 by his "heredity." Mentality, morality, conduct, career, 

 fate, are affected by the hereditary materials with which the 

 individual starts life. 



The truth of this conclusion came out still more strongly 

 when the detailed records of the twins were studied. In the 

 case of the single-egg twins, the two members conducted 

 themselves as duplicate personalities might be expected to 

 do. One such twin was a burglar; on looking up his brother's 

 record, he was found to be a burglar too. In another pair, 

 one twin was a high-powered financial swindler, fraudu- 

 lently collecting large sums from his dupes. And so also was 

 the other twin of that pair. Besides the pair that were 

 burglars, and the pair that were swindlers, another pair 

 of one-egg twins both "committed puerile offenses against 

 the property laws." Another consisted, In the words of 

 Lange, of "gutter-snipes, but good fellows at heart," 

 though they "cannot stand alcohol; it develops frenzy and 

 draws the knives from their pockets." Another pair de- 

 scribed "have too little sense and will power," while in still 

 another, both "are lacking in all human feeling except for 

 their own unpleasant selves." And so goes the account 

 throughout the entire list; the similarity In conduct Is aston- 

 ishing. Lange says, "In all these pairs the type of crime is 



