3 6 THE POPULAR SCIENCE MONTHLY. 



deductively from the principles of the instability of the homogeneous 

 and the multiplication of effects. How far Mr. Spencer was here in 

 advance of all other workers in this field will appear, when we con- 

 sider that the doctrine of Evolution, as it now stands, was thus, in its 

 universality, and in its chief outlines, announced by him two years be- 

 fore the appearance of Mr. Darwin's " Origin of Species." 



A principle of natural changes more universal than any other 

 known, applicable to all orders of phenomena, and so deep as to in- 

 volve the very origin of things, having thus been established, the final 

 step remained to be taken, which was, to give it the same ruling place 

 in the world of thought and of knowledge that it has in the world of 

 fact and of Nature. A principle running through all spheres of phe- 

 nomena must have the highest value for determining scientific rela- 

 tions; and a genetic law of natural things must necessarily form the 

 deepest root of the philosophy of natural things. It was in 1858, as 

 Mr. Spencer informs me, while writing the article on the " Nebular 

 Hypothesis," that the doctrine of Evolution presented itself as the 

 basis of a general system under which all orders of concrete phenom- 

 ena should be generalized. Already the conception had been traced 

 out in its applications to astronomy, geology, biology, psychology, as 

 well as all the various super-organic products of social activity ; and 

 it began to appear both possible and necessary that all these various 

 concrete sciences should be dealt with in detail from the Evolution 

 point of view. By such treatment, and by that only, did it appear 

 practicable to bring them into relation so as to form a coherent body 

 of scientific truth a System of Philosophy. 



It is proper in this place to state that, in contemplating the execu- 

 tion of so comprehensive a work, the first difficulty that arose was a 

 pecuniary one. Mr. Spencer had frittered away the greater part of 

 what little he possessed in writing and publishing books that did not 

 pay their expenses, and a period of eighteen months of ill-health and 

 enforced idleness consequent on the writing of one of them had fur- 

 ther diminished his resources. His state of health was still such that 

 he could work, at the outside, but three hours a day, and very fre- 

 quently not even that, so that what little he could do in the shape of 

 writing for periodicals, even though tolerably paid for it, did not suf- 

 fice to meet the expenses of a very economical bachelor-life. How, 

 then, could he reasonably hope to prosecute a scheme elaborating the 

 doctrine of Evolution throughout all its departments in the way con- 

 templated a scheme that would involve an enormous amount of 

 thought, labor, and inquiry, and which seemed very unlikely to bring 

 any pecuniary return, even if it paid its expenses ? Unable to see 

 any solution of the difficulty, Mr. Spencer wrote, in July, 1858, to 

 Mr. John Stuart Mill, explaining his project, and asking whether he 

 thought that in the administration for India, in which Mr. Mill held 

 office, there was likely to be any post, rather of trust than of much 



