THE FOUNDATION OF EVOLUTION 



numerous and incontrovertible, at his disposal. In 

 this respect Spencer was greatly indebted to the 

 labors of the first half of the nineteenth century. 

 The chief intellectual achievement of that period 

 was the establishment of the doctrine of the con- 

 servation of energy ; and upon this doctrine Spencer 

 founded his philosophy. 



His predecessors were not always so wise. 

 Philosophies have ere now been founded on the 

 shifting sand of a priori ideas, reached in a "flash" 

 of misbegotten inspiration ; they have been reared 

 in defence of religious dogma, in support of moral 

 laws supposed to be in danger of neglect or denial, 

 and even upon the sheer egoism of the philosopher. 

 Many bold prophets have arisen who professed 

 unmitigated contempt for the science of their 

 time, as did the undoubtedly great Hegel, who not 

 merely ignored the law of gravitation in his specu- 

 lations, but spent much satire and time in an at- 

 tempt to overthrow, or at least to scarify, the ada- 

 mantine work of Newton. Spencer, however, had 

 a unique opportunity, and took it at the flood. 



The use of the word energy we owe to Dr. Thomas 

 Young, the decipherer of hieroglyphics and founder 

 of the undulatory theory of light. The doctrine of 

 the conservation of energy was preceded by that 

 which declares that matter is eternal. Spencer 

 accepted this dogma of the conservation of matter, 

 though, as we shall see, he objected to the use of 

 the term conservation as implying a conserver. 

 The one chapter in First Principles that has not 

 4 39 



