PREFACE 



THE present work is based upon lectures 

 given at Harvard University in the au- 

 tumn of 1869, ^^^ spring of 1871, and 

 afterwards repeated, wholly or in part, in Bos- 

 ton, New York, Milwaukee, and London.^ 



At the outset these lectures were designed 

 to include only a criticism of the Positive Phi- 

 losophy, 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 lec- 

 tures were reported in the New York " World," 

 and seemed to meet the wants of a large num- 

 ber 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 Doc- 

 trine 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 

 ^ [See Introduction, § 3.] 

 vii 



