18 TROPISMS 



the individual or the race. 5 The Aristotelians had ex- 

 plained the processes in the inanimate world in the same 

 teleological way. Science began when Galileo overthrew 

 this Aristotelian mode of thought and introduced the 

 method of quantitative experiments which leads to mathe- 

 matical laws free from the metaphysical conception of 

 purpose. The analysis of animal conduct only becomes 

 scientific in so far as it drops the question of purpose 

 and reduces the reactions of animals to quantitative laws. 

 This has been attempted by the tropism theory of ani- 

 mal conduct. 



i> Tills view is still held, especially among authors, who lean more or 

 less openly to vitalism, e.g., v. Uexkiill, Jordan, Franz, Bauer, Budden- 

 brock, and others. 



