PREFACE. 



The present work is based upon lectures given at Harvard 

 University in the autumn of 1869 and spring of 1871, and 

 afterwards repeated, wholly or in part, in Boston, New York, 

 Milwaukee, and London. 



At the outset these lpctures were designed to include 

 only a criticism of the Positive Philosophy, and I had 

 no intention of publishing them in anything like the 

 shape in which they were originally written. It was 

 only when — at the suggestion of Dr. E. L. Youmans, and 

 through the kindness of Mr. Marble — the lectures were 

 reported in the New York World, and seemed to meet 

 the wants of a large number of readers, that I decided 

 upon publishing them, and upon so enlarging the course 

 as to make it include a somewhat complete outline - 

 sketch of the new philosophy based on the Doctrine of 

 Evolution. In coming to this decision, I was at first but 

 carrying out a project, formed several years earlier, of 

 writing a series of essays illustrative of Mr. Spencer's 

 philosophy. But the work has grown on my hands, and 

 in its present shape is something more than it was originally 

 intended to be. For while it does not, as a whole, lay any 

 claim to the character, of an original work, it has never- 

 theless come to contain so much new matter, both critical 

 and constructive, that it can no longer be regarded as a mere 

 reproduction of Mr. Spencer's thoughts. The new con- 



