MECHANISM OF NATURE 



Identical life of an identical form cannot be a 

 primary identity, because it is reproduced and 

 grows with the growth of the identical form. 



Is there a similar life made for every similar 

 form? 



Do these lives lie around waiting for a form that 

 fits them? 



Surely not, for life must reproduce the form, and 

 form must reproduce the life. 



Therefore, identical life is the necessary result 

 of identical form. 



PROPOSITION XXV. 



Everything we can directly perceive is a living 

 identity or a compound of living identities. 



There is evidently a vast difference between the 

 sun we can directly perceive and the material 

 which lies between us and the sun. 



Because, sun and earth and planets have regular 

 orbits, which we can compute; therefore, it is evi- 

 dent that universal force, both in the manifesta- 

 tion of imparted momentum and in restraining 

 gravity, works entirely different on the great num- 

 ber of primary spheres which intervene between the 

 heavenly bodies and themselves. 



But all bodies are composed of primary spheres 

 (Prop. XIX, B. 1), and the same force cannot 

 make a different change in similar material if 



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