SCIENCE AND PHILOSOPHY 161 



feel sure that organisms reveal a deeper aspect 

 of reality than crystals do, and that in this sense 

 there is more in the plant than in the crystal, 

 more in the animal than in the plant, more in 

 the bird than in the worm, more in man than in 

 them all. 



Let us try to state our personal position in a 

 few words. With our biological prepossessions 

 it seems clear to us that students of science would 

 breathe more freely if they could rid themselves 

 of the influence of the hypothesis, so character- 

 istic of Kant, that there is but one science of 

 Nature and that the category of mechanism is 

 the only one we need. It seems to us that there 

 are several sciences of Nature, and that other 

 than mechanical categories are required in two 

 of these. 



(1) There is the physical order of Nature 

 the inorganic world where mechanism reigns 

 supreme. (2) There is the vital order of Nature 

 the world of organisms where mechanism proves 

 insufficient. (3) There is the psychical order of 

 Nature the world of mind where mechanism 

 is irrelevant. Thus there are three fundamen- 

 tal sciences Physics, Biology, and Psychology 

 each with characteristic questions, categories and 

 formulae. 



It is evident, indeed, that the physical order 

 overlaps the vital, for the life of the organism 



