XIV PEEFACE. 



as well as scientific culture. Nor could he fully compre- 

 hend the Kantian argument for Free-will, nor for a 

 Future Life, nor for the imperative of Morality, which 

 are briefly considered in the several chapters devoted to 

 these topics, without more knowledge of Kant's system 

 than is to be gathered from the exposition itself. But 

 even as regards Kant I have tried to simplify the expo- 

 sition so that those who have a tincture of philosophy 

 may understand it, while, this philosopher's speculations 

 apart, and they do not occupy much space, the remainder 

 of the above chapters, and in fact, the whole remainder of 

 the book, with the exception above stated of chapter i., 

 and a small portion of chapters ii. and iii. of the third 

 part, ought to be very generally intelligible. 



The first two books have each a certain completeness 

 in themselves. But some controversies, only partially 

 treated in the first chapter of the book, are postponed, 

 as regard their full treatment, to the third book, which 

 is in some respects an appendix. This separation has 

 been objected to, as needless, by an eminent naturalist * 

 who has criticized the book, and by the reviewer in 

 Mind, as resulting in repetition. But, once again, 

 my chief reason was consideration for the reader. 

 Further, I did not wish to impair the interest of 

 the book. The two first chapters of the third part, 

 which are logically connected with the first chapter in 

 the book, are mainly controversial in character, and the 

 argument is close, severe, and somewhat long, and I did 

 * Professor Asa Gray. 



