PHILOSOPHY OF NATURE -LEIBNITZ'S IDEAS. 35 



what are the latter's mutual relations ? On this subject 

 Leibnitz develops completely original ideas. Souls are 

 monads of more perfect kind and higher activity, the prin- 

 ciples of all those forces that are specially translated into 

 organization, life, thought, etc. There are souls every- 

 whereif not thinking souls, at least forces that have the 

 power of occasioning appearances resembling those of life. 

 Leibnitz thus holds that the number of souls is infinite, and 

 that there is no portion of matter, how small soever it may 

 be, in which a living actuality is not always found ; but, 

 just as the monads of mere matter are manifested by it, the 

 monads of organized matter are manifested by organization. 

 The perfection of the substance accords with, and is propor- 

 tioned to, that of its original. While Descartes makes an 

 essential separation between soul and body, Leibnitz can- 

 not conceive of them apart. He says distinctly, in the 

 " New Essays," " The soul is never separated from some 

 kind of a body ; " and he writes to Arnauld, " Our body is 

 the matter, and our own soul is the form, of our substantial 

 existence." We find exactly the same propositions in 

 several of his works, especially in the " Monadology." The 

 rational soul must be distinguished from the sentient soul. 

 Animals, in the condition of germs, have only sentient 

 souls ; but, as soon as those germs are elected, and arrive at 

 a perfect nature, their sentient souls are raised to the pre- 

 rogative of reason. 



The reasoning soul is, for Leibnitz, the source of all 

 highest revelation. The foundation of things, as he holds, 

 is everywhere the same, and we must judge of every thing 

 according to that which is known to us, that is, the soul. 

 Our self is, in fact, the only substance of which we have 

 direct consciousness. The true unity we feel to exist in 

 it we must attribute to other substances, just as we must 

 judge of force, not as an object of the senses and the 

 imagination, but in accordance with that type which we 



