DARWIN AND THE ORIGIN OF SPECIES 217 



truth and extent of those facts none but men possessing a 

 special knowledge of physiology and natural history have any 

 right to an opinion ; but the superstructure based on those 

 facts enters the region of pure reason, and may be discussed 

 apart from all doubt as to the fundamental facts. 



Can natural selection choose special qualities, and so breed 

 special varieties as man does ? Does it appear that man has 

 the power indefinitely to magnify the peculiarities which dis- 

 tinguish his breeds from the original stock ? Is there no other 

 evidence than that of geology as to the age of the habitable earth ? 

 and what is the value of the geological evidence ? How far, in 

 the absence of other knowledge, does the mere difficulty in 

 classifying organised beings justify us in expecting that they 

 have had a common ancestor ? And finally, what value is to 

 be attached to certain minor facts supposed to corroborate the 

 new theory ? These are the main questions to be debated in 

 the present essay, written with a belief that some of them have 

 been unduly overlooked. The opponents of Darwin have been 

 chiefly men having special knowledge similar to his own, and 

 they have therefore naturally directed their attention to the 

 cardinal facts of his theory. They have asserted that animals 

 are not so similar but that specific differences can be detected, 

 and that man can produce no varieties differing from the parent 

 stock, as one species differs from another. They naturally 

 neglect the deductions drawn from facts which they deny. If 

 your facts were true, they say, perhaps nature would select 

 varieties, and in endless time all you claim might happen ; 

 but we deny the facts. You produce no direct evidence that 

 your selection took place, claiming only that your hypothesis is 

 not inconsistent with the teaching of geology. Perhaps not, but 

 you only claim a c may be,' and we attack the direct evidence 

 you think you possess. 



To an impartial looker-on the Darwinians seem rather to 

 have had the best of the argument on this ground, and it is at 

 any rate worth while to consider the question from the other 

 point of view; admit the facts, and examine the reasoning. 

 This we now propose to do, and for clearness will divide the 

 subject into heads corresponding to the questions asked above, 

 as to the extent of variability, the efficiency of natural selection, 



