viii PREFACE. 



he has been indebted to several important treatises, 

 partly historical and partly philosophical, on the 

 generalities and processes of physical science, which 

 have been published within the last few years. To 

 these treatises, and to their authors, he has endea- 

 voured to do justice in the body of the work. But 

 as with one of these writers, Dr. Whewell, he has 

 occasion frequently to express differences of opinion, 

 it is more particularly incumbent on him in this 

 place to declare, that without the aid derived from 

 the facts and ideas contained in that gentleman's 

 History of the Inductive Sciences, the corresponding 

 portion of this work would probably not have been 

 written. 



The concluding Book is an attempt to contribute 

 towards the solution of a question, which the decay 

 of old opinions, and the agitation that disturbs Euro- 

 pean society to its inmost depths, render as impor- 

 tant in the present day to the practical interests of 

 human life, as it must at all times be to the com- 

 pleteness of our speculative knowledge : viz. Whether 

 moral and social phenomena are really exceptions to 

 the general certainty and uniformity of the course of 

 nature ; and how far the methods, by which so many 

 of the laws of the physical world have been numbered 

 among truths irrevocably acquired and universally 

 assented to, can be made instrumental to the forma- 

 tion of a similar body of received doctrine in moral 

 and political science. 



