The Doctrine of Evolution. 441 



problem was really one of the most complicated and abstruse 

 that the scientific mind has ever grappled with. Starting 

 from the known experiences of breeders of domestic animals 

 and cultivated plants, and duly considering the remarkable 

 and sometimes wonderful changes that are wrought by the 

 simple process of selection, the problem before Mr. Darwin 

 was to detect among the multifarious phenomena of organic 

 nature any agency capable of accomplishing what man thus 

 accomplishes by selection. In detecting the agency of natu- 

 ral selection, working perpetually through the preserva- 

 tion of favored individuals and races in the struggle for ex- 

 istence, Mr. Darwin found the vera causa for which men 

 were waiting. With infinite patience and caution he applied 

 his method of explanation to one group of organic phenomena 

 after another, meeting in every quarter with fresh and often 

 unexpected verification. He had the satisfaction of living 

 to see pretty much the whole contemporary world of zoolo- 

 gists, botanists, and palaeontologists pursuing the lines of 

 investigation which he had laid down and in general agree- 

 ment as to the fundamental principle. There was a general 

 acquiescence in natural selection as an agency capable of 

 working specific changes, while further speculation and in- 

 vestigation in all directions were employed in ascertaining 

 the precise character of its work and determining the limits 

 of its efficacy. That all the phenomena of the organic world 

 can be accounted for by natural selection, Mr. Darwin never 

 at any time supposed ; nor was he ever so silly as to suppose 

 that all difficulties had been removed by himself or were 

 likely to be removed within a single generation by the collect- 

 ive work of the whole scientific world. The present gener- 

 ation has witnessed a tendency toward restricting the proba- 

 ble limits of the efficacy of natural selection, followed by an 

 equally marked tendency toward enlarging them a tendency 

 likely to be furthered by Mr. "Wallace's recent book, point- 

 ing out the great extent of variation that normally goes on 

 within the limits of one and the same species. Such minor 

 fluctuations in scientific theory occur in all departments of 

 inquiry, but no one doubts the essential soundness of the 

 Darwinian theory, and as for the doctrine of special crea- 

 tions which it superseded, we shall probably go back to it 

 when we go back to stone arrow-heads and the primitive 

 Aryan ox-cart, and not before. 



It has more than once been observed that, when a new 

 discovery in science is announced to the world, people at 

 30 



