52 THE GROWTH OF GROUPS 



speak of a typical individual when we are dealing with 

 one measurable feature at a time." Professor Karl 

 Pearson, commenting adversely on these words, upheld, as 

 I thought, the contrary opinion, that the normal man is 

 a reality.* Either I misunderstood him or he has since 

 changed his view, for he has recently given his opinion 

 as follows : "... to define the normal person. There 

 is no such person. "f It seems that the " reality " of the 

 normal man is no longer defensible. 



Being much impressed with the truth of the Mutation 

 Theory I regard a species as a number of animals each 

 possessing characters A, B, C, etc. Any animal having 

 these characters is a normal member of the species. An 

 individual who has one or more characters in addition 

 to A, B, C, etc., may be called an abnormal member of 

 that species, but only for convenience in order to express 

 the fact that it is in the minority. 



Further, it seems that every extensive group of living 

 things appears to be polymorphic, if it be examined 

 closely enough. That is to say, some members of the 

 group will possess characters which are absent from 

 others. We can see dimly that this is true even of 

 mankind. The chief quality of man, that makes him 

 man, so to speak, is his mind ; but this attribute does 

 not appear to be one thing, present in varying degrees. 

 On the contrary, the mental endowment of an individual 

 appears to be a number of attributes, some of which, 

 being present in almost all, may be called normal, others, 

 being present in few, are abnormal. Though the human 

 mind in general is so complex that any representation 

 of it must be dim, yet it seems possible to perceive that 



* " Biometrica," 1911. t Daily Mail, May 20, 1912. 



