Herbert Spencer and the l\h trine ttwn. 517 



the fourth part of the work, under the title of Spe< ial 

 thesis, the Involution is traced out under its concrete : 

 from reflex action up through instinct, memory. 

 feelings, and the will. Mr. Spencer here distinctly avowed 

 his belief that " life in its multitudinous and infinitely 

 varied embodiments has arisen out of the lowest and sim- 

 plest beginnings, by steps as gradual as those which evolve 

 a homogeneous microscopic germ into a complex organism " 

 dissent being at the same time expressed from that 

 version of the doctrine put forth by the author of the Ves- 

 tiges of the Natural History of Creation. It was, more- 

 over, shown by subjective analysis how intelligence may 

 be resolved, step by step, from its most complex into its 

 simplest elements, and it was also proved that there is 

 " unity of composition " throughout, and that thus mental 

 structure, contemplated internally, harmonizes with the 

 doctrine of Evolution. 



It was at this time (1854), as I have been informed by 

 Mr. Spencer, when he had been at work upon the Princi- 

 ples of Psychology not more than two months, that the 

 general conception of Evolution in its causes and extent, 

 as well as its processes, was arrived at. He had somewhat 

 earlier conceived of it as universally a transformation from 

 the homogeneous into the heterogeneous. This kind of 

 change, which Von Baer had shown to take place in every 

 individual organism, as it develops, Mr. Spencer had already 

 traced out as taking place in the progress of social arrange- 

 ments, in the development of the sciences, and now in the 

 Evolution of mind in general from the lower forms to the 

 higher. And the generalization soon extended itself so as 

 to embrace the transformations undergone by all things 

 inanimate as well as animate. This universal extension of 

 the idea led rapidly to the conception of a universal cause 

 necessitating it. In the autumn of 1854, Mr. Spencer pro- 

 posed to the editor of the Westminster Review to write 



