Masterpieces of Science 



of attraction; notwithstanding that Leibnitz 

 formerly accused Newton of introducing "occult 

 qualities and miracles into philosophy." 



I see no good reasons why the views given in 

 this volume should shock the religious feelings 

 of any one. It is satisfactory, as showing how 

 transient such impressions are, to remember that 

 the greatest discovery ever made by man, namely, 

 the law of the attraction of gravity, was also 

 attacked by Leibnitz, "as subversive of natural, 

 and inferentially of revealed religion. " A 

 celebrated author and divine has written to me 

 that "he has gradually learned to see that it is 

 just as noble a conception of the Deity to believe 

 that He created a few original forms capable of 

 self-development into other and needful forms, as 

 to believe that He required a fresh act of creation 

 to supply the voids caused by the action of His 

 laws. " 



Why, it may be asked, until recently did nearly 

 all the most eminent living naturalists and geo- 

 logists disbelieve in the mutability of species ? 

 It cannot be asserted that organic beings in a 

 state of nature are subject to no variation; it can- 

 not be proved that the amount of variation in the 

 course of long ages is a limited quantity; no clear 

 distinction has been, or can be, drawn between 

 species and well-marked varieties. It cannot be 

 maintained that species when intercrossed are 

 invariably sterile and varieties invariably fertile ; 

 or that sterility is a special endowment and sign 

 of creation. The belief that species were im- 

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