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- 
where—if 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 se/f 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 
