ENVIRONMENT AMONG MEN 351 



to which I refer, were non-contagious, or, if contagious, the twins 

 caught them simultaneously ; they did not catch them the one 

 from the other. This implies so intimate a constitutional re- 

 semblance, that it is proper to give some quotations in evidence,' ^ 

 and he proceeds to give detailed evidence. Later he remarks 

 on the ' similarity in the association of ideas. No less than 

 11 out of the 35 cases testify to this. They make the same 

 remarks on the same occasions, begin singing the same song at 

 the same moment and so on."-^ With regard to tastes and dis- 

 positions Galton says that ' in 16 cases — that is in nearly one- 

 half of them — these were described as closely similar ; in the 

 remaining 19 they were much alike, but subject to certain named 

 differences. These differences belonged almost wholly to such 

 groups of qualities as these : the one was more vigorous, fearless, 

 energetic, the other was gentle, clinging, and timid ; or the one 

 was more ardent, the other more calm and placid ; or again the 

 one was the more independent, original, and self-contained ; 

 the other the more generous, hearty, and vivacious. In short the 

 difference was that of intensity or energy in one or other of its 

 protean forms ; it did not extend more deeply into the structures 

 of the characters. The more vivacious might be subdued by 

 ill health, until he assumed the character of the other ; or the 

 latter might be raised by excellent health to that of the former. 

 The difference was in the key-note, not in the melody.' ^ Galton 

 sums up the evidence as follows : ' It follows from w^hat has been 

 said concerning the similar dispositions of the twins, the similarity 

 in the association of their ideas, of their special ailments, and of 

 their illnesses generally, that the resemblances are not superficial, 

 but extremely intimate. I have only two cases of a strong bodily 

 resemblance being accompanied by mental diversity, and one 

 case only of the converse kind.'^ 



It has to be remembered that up to this period the twins had 

 been reared under very similar conditions indeed ; Galton in 

 fact says that they had been reared ' exactly alike '.^ He goes 

 on to ask what changes were produced when they left the family 

 and went out into the world. He sums up the result of his 

 inquiries into this point as follows : ' Here are 35 cases of twins 

 who were " closely ahke " in body and mind when they were 



1 Galton. loc. cit,. p. 226. « Ibid., p. 231. » Ibid. * Ibid., p. 232. 



» Ibid., p. 233. 



