iv Dedicatory Epistle 



sion. My theory of the causes and effects of the 

 prolongation of human infancy, with reference to 

 the evolution of man, was first published in the 

 "North American Review" for October, 1873, 

 when you were the editor of that periodical. The 

 article, which was entitled "The Progress from 

 Brute to Man," was made up of two chapters of 

 my " Outlines of Cosmic Philosophy " (part ii. 

 chaps, xxi., xxii.), which was published a year 

 later, in October, 1874. The value of the theory 

 therein set forth was at once recognized by many 

 leading naturalists. In the address of Vice-Presi- 

 dent Edward Morse, before the American Associa- 

 tion, at its meeting at Buffalo in 1876, my theory 

 receives extended notice as one of the most impor- 

 tant contributions yet made to the Doctrine of Evo- 

 lution ; and it is declared that I have given " for 

 the first time a rational explanation of the origin 

 and persistence of family relations, and thence 

 communal [i. e., clan] relations, and, finally, of 

 society." 1 



Uncontrollable circumstances have prevented 

 my giving to the further elaboration of this infancy 

 theory the time and attention which it deserves 



1 Morse, What American Zoologists have done for Evolution, 

 pp. 37, 39-41, Salem, 1876 ; Proc. Amer. Assoc. for Adv. of Sci., 

 vol. xxii 



