PHILOSOPHY OF NATURE LEIBNITZ'S IDEAS. 39 



that precede it. On the other hand, monads, in their in- 

 finite diversities, succeed each other without a break from 

 the most rudimentary to the most perfect ones. That pro- 

 gression which we conceive of in the abstract quantities 

 of mathematics exists among the .real quantities of the 

 world, which monads of every kind are. Force, life, will, 

 are assigned in different proportions to all the degrees of 

 that immeasurable series in the lower ones dull and imper- 

 ceptible, in the higher ones potent and fruitful. The pas- 

 sage of inferior monads to higher planes takes place gradu- 

 ally through a thousand intermediate ones. The principles 

 of bodies advance incessantly nearer to perfection, and do 

 not differ essentially from those of the souls with which 

 they are connected. Souls in their turn are numerous, and 

 they too obey a law of progress. Thus there is a measure- 

 less quantity of degrees of life, some more or less dominant 

 over others, from the faint and dull activity of the atom of 

 sand up to the sovereign power of absolute mind. Des- 

 cartes had said that all the facts of Nature follow on in 

 connection like geometric truths. Leibnitz shows us a yet 

 deeper and more universal order in things. Every thing 

 is proportioned, analogous, harmonious : all is held, is con- 

 tinued, in unbroken interdependence. Thus we no longer 

 recognize two distinct worlds, the natural and the spiritual 

 one. Spiritual existences compose a part of one and the 

 same series with corporeal ones. The only differences be- 

 tween them are differences of degree. 



The principle of the " sufficient reason " discloses to us 

 the strict economy of things. Nothing occurs in Nature 

 without a reason, but she is not wasteful of her reasons. 

 She always chooses the shortest ways. Magnificent in 

 effects, miserly in causes, she produces the greatest amount 

 of work with the least amount of force. The reasons of 

 the world, Leibnitz holds, are hidden in something extra- 

 mundane, which differs from the interdependence of states, 



