TRANSLATOR'S NOTE 



IN the opening chapter of the Origin of Species Darwin 

 states that the * variability/ on which selection and 

 adaptation have to work, ' is governed by many unknown 

 laws/ 



In translating a book which fills this gap in the 

 Evolutionary Theory by assigning a psychic cause as 

 the origin of Variation (thus traversing the arguments 

 of later biologists who refer that origin to chance or to 

 the pressure of the environment) ; a book which modifies 

 the conclusions of many schools of thought, both new 

 and old; which replaces Bergson's famous elan vital 

 by a concrete energy, and defines that energy as an 

 influence forming all the varieties of cellular tissue out 

 of one primordial substance, and moulding those tissues 

 into organic form under the impulsion of a Directing 

 Idea, the translator has a most responsible task. 



One duty, and one only, lies upon him to be 

 faithful to the author's meaning. No attempt at literary 

 finish can palliate or excuse the slightest departure from 

 that duty in a work which, however scientific in essence, 

 is necessarily somewhat controversial in form. When 

 to this duty there are added the obligations which the 

 honour of personal friendship involves, faithfulness in 

 rendering the idea becomes doubly imperative. To 

 this all other considerations must give place. 



The Italian adage, ' Traduttori traditori,' is one 

 which the translator must ever bear in mind if he would 

 not be a traitor also. He has therefore kept a number 

 of words which, though used by classical English writers 

 on philosophy, may seem more or less uncouth and 

 foreign to those who are unfamiliar with such authors. 

 It is quite inevitable that a book which presents an 

 entirely new application and extension of psychology 



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