LECTURE VI. 



A CRITICAL EXAMINATION OF THE POSITION OF 

 MR. DARWIN'S WORK, "ON THE ORIGIN OF 

 SPECIES," IN RELATION TO THE COMPLETE 

 THEORY OF THE CAUSES OF THE PHENOME- 

 NA OF ORGANIC NATURE. 



In the preceding five lectures I have endeavoured to 

 give you an account of those facts, and of those reason- 

 ings from facts, which form the data upon which all 

 theories regarding the causes of the phenomena of or- 

 ganic nature must be based. And, although I have had 

 frequent occasion to quote Mr. Darwin — as all persons 

 hereafter, in speaking upon these subjects, will have 

 occasion to quote his famous book on the " Origin of 

 Species," — you must yet remember that, wherever I 

 have quoted him, it has not been upon theoretical 

 points, or for statements in any way connected with his 

 particular speculations, but on matters of fact, brought 

 forward by himself, or collected by himself, and which 

 appear incidentally in his book. If a man icill make 

 a book, professing to discuss a single question, an en- 

 cyclopaedia, I cannot help it. 



Now, having had an opportunity of considering in 

 this sort of way the different statements bearing upon 

 all theories whatsoever, I have to-night to lay before 



