174 THE ORIGIN OF SPECIES 



species in Nature, has ever been originated by selection, 

 whether artificial or natural. Groups having the morpho- 

 logical character of species, distinct and permanent races 

 in fact, have been so produced over and over again ; but 

 there is no positive evidence, at present, that any group of 

 animals has, by variation and selective breeding, given 

 rise to another group which was even in the least degree infer- 

 tile with the first. Mr. Darwin is perfectly aware of this 

 weak point, and brings forward a multitude of ingenious and 

 important arguments to diminish the force of the objection. 

 We admit the value of these arguments to their fullest 

 extent ; nay, we will go so far as to express our belief that 

 experiments, conducted by a skilful physiologist, would very 

 probably obtain the desired production of mutually more 

 or less infertile breeds from a common stock, in a compara- 

 tively few years ; but still, as the case stands at present, this 

 "little rift within the lute" is not to be disguised nor over- 

 looked. 



In the remainder of Mr. Darwin's argument our own 

 private ingenuity has not hitherto enabled us to pick holes 

 of any great importance ; and judging by what we hear and 

 read, other adventurers in the same field do not seem to have 

 been much more fortunate. It has been urged, for instance, 

 that in his chapters on the struggle for existence and on 

 natural selection, Mr. Darwin does not so much prove that 

 natural selection does occur, as that it must occur ; but, in 

 fact, no other sort of demonstration is attainable. A race 

 does not attract our attention in Nature until it has, in all 

 probability, existed for a considerable time, and then it is 

 too late to inquire into the conditions of its origin. Again, 

 it is said that there is no real analogy between the selection 

 which takes place under domestication, by human influence, 

 and any operation which can be effected by Nature, for man 

 interferes intelligently. Reduced to its elements, this 

 argument implies that an effect produced with trouble by an 

 intelligent agent must, d fortiori, be more troublesome, if 

 not impossible, to an unintelligent agent. Even putting 

 aside the question whether Nature, acting as she does accord- 

 ing to definite and invariable laws, can be rightly called an un- 

 intelligent agent, such a position as this is wholly untenable. 

 Mix salt and sand, and it shall puzzle the wisest of men, with 

 his mere natural appliances, to separate all the grains of sand 

 from all the grains of salt ; but a shower of rain will effect 

 the same obj ect in ten minutes. And so, while man may find 



