Evolution of Evolution-Theory. 221 



which possesses it, and to extend the dimensions of its 

 parts up to a limit which it itself imposes. [The Law 

 of Growth.] 



II. The production of a new organ in an animal body 

 results from a new need which continues to be felt, and 

 from a new movement which this need originates and 

 sustains. [The Law of Functional Reaction.] 



III. The development of organs and their power of 

 action are always in proportion to the functioning of 

 these organs. [The Law of Use and Disuse.] 



IV. All that has been acquired, trac6, or changed in 

 the structure of individuals during the course of their 

 life is preserved by generation [heredity], and trans- 

 mitted to new individuals which proceed from those 

 that have undergone these changes. [The Law of Use- 

 Inheritance.] 



Johann Wolfgang Goethe (1749-1832), "the greatest 

 poet of evolution ", took into his skilled hands the lyre 

 which Empedocles had tuned, but which, since the time 

 of Lucretius, had given forth no music. Even Erasmus 

 Darwin only wrote prose in verse. We cannot in our 

 partiality repress the futile wish that Goethe had loved 

 poetry less and science more, since his was certainly 

 one of the greatest intellects that has ever dealt with 

 evolution problems. Profoundly influenced by the 

 Greeks, by the Naturphilosophie, and by Buffon, he 

 remained unfortunately ignorant of Lamarck, just as 

 the latter was unaware of Erasmus Darwin, all of 

 which seems strange to us to-day, when a professor in 

 a small university town in Germany can scarce give a 

 lecture of moment without its being echoed through 

 three continents. Although Goethe was a thorough- 

 going evolutionist, combining the theories of Buffon 

 and Lamarck, his main contribution to aetiology was 

 in great part indirect, through his development of the 

 principles of morphology. He placed the theory of 

 homologies on a securer basis, and elaborated the con- 

 ception of " unity of type " (1796), which has had such 

 a persistent influence on morphological studies. Goethe 

 was also one of those who see in evolution an expression 

 of laws of growth, and seem to have hold of some idea 



