Chap. I.] Mechanical Philosophy. 19 



chitlson*s voluminous writings had nearly disap- 

 peared*. 



Another opponent' of the Newtonian system was 

 Godfred WiUiam Leibnitz, a philosopher of Lcipsic, 

 in Germany, whose celebrated theory demands our 

 notice. He taught that the whole universe is 

 made up of monads, that is, simple substances with- 

 out parts or figure, each of which is, by the Creator, 

 in the beginning of its existence, endowed with 

 certain active and perceptive powers, sufficient to 

 produce all the changes which it undergoes, from 

 the beginning to eternity ; which changes, though 

 they ma}^ seem to us to be the effects of causes 

 operating from without, are only the gradual and 

 successive evolutions of the monad^s own internal 

 powers, which would have produced the same mo- 

 tions and changes, although there had been no 

 other being in the universe. He supposed, farther, 

 that the universe is completely filled with monads, 

 without any chasm or void, and thereby every 

 body acts upon every other body, according to its 

 vicinity or distance, and is mutually reacted upon by 

 every other body ; hence he considered every mo- 

 nad as a kind of living mirror, which reCccts tlie 

 ^vhole universe, according to its point of view, and 

 represents the whole more or less distinctly. The 

 adoption of this visionary system led Leibnitz to 

 oppose, with considerable warmth, several of tne 

 leading doctrines of Newton, and espec ally his 

 great principle of gravitation. Tiie hostility of tlie 

 German philosopher toward the illustrious Hntou 

 was particularly displayed in his contiovci jy with 



* See Additional Notes — (B). 

 C 2 



