286 FROM THE GREEKS TO DARWIN 



Treviranus thus ranges himself with the school 

 of Buffon, Lamarck, Geoffroy St. Hilaire, and 

 Goethe, as against the school of Linnseus and 

 Cuvier. He believes it possible to discover the 

 philosophy of Nature, and his whole work is writ- 

 ten in an admirable spirit. In the succeeding in- 

 troductory chapters upon the interpretation of 

 living Nature, he considers the importance of 

 biology, its fundamental principles, possible sys- 

 tems, methods of experimental biology, as well 

 as the use of the hypothesis — that is, the working 

 hypothesis — as the essential weapon of progress 

 toward the truth. He defines biology as "the study 

 of the different forms and appearances of organic 

 life, of the conditions and laws under which these 

 exist, and of the causes by which they are kept in 

 operation." He points out^ that every part of the 

 organism is subservient to the whole, that Nature 

 never builds up one organ or system of organs 

 without causing others to suffer reduction. This 

 is equivalent to the 'lot de balancemenf of St. 

 Hilaire, or the modern law of ^compensation of 

 growth,' the deficiency of one part being made 

 up by the greater development of another. He 

 also, as clearly as Lamarck, perceives the causal 

 relation between function and structure. In his 

 conception of natural environment, he wuth 

 Schelling perceives that every class of animals 



"^Loc. cit., p. 58. 



