DARWIN'S THEORY IS ADEQUATE 391 



I recently read an essay in which the writer is good 

 enough to say that, owing to the work of Darwin, the fact 

 that the differences which we see between organisms have 

 been reached by a gradual evolution, is not now disputed. 

 That, at any rate, seems to be a solid achievement. But 

 he went on to declare that when we inquire by what method 

 this evolution was brought about biologists can return no 

 answer. That appears to me to be a most extraordinary 

 perversion of the truth. The reason why the gradual 

 evolution of the various kinds of organisms is not now 

 disputed is that Darwin showed the method by which 

 that evolution can and must be brought about. So far 

 from " returning no answer," Darwin and succeeding 

 generations of biologists do return a very full answer to 

 the question, " By what method has organic evolution 

 been brought about ?" Our misleading writer proceeds 

 as follows : "The Darwinian theory of natural selection 

 acting on minute differences is generally considered 

 nowadays to be inadequate, but no alternative theory has 

 taken its place." This is an entirely erroneous statement. 

 Though Darwin held that natural selection acted most 

 widely and largely on minute differences, he did not 

 suppose that its operation was confined to them, and he 

 considered and gave importance to a number of other 

 characteristics of organisms which have an important part 

 in the process of organic evolution. The assertion that 

 the theory of natural selection as left by Darwin " is now 

 generally held to be inadequate " is fallacious. Darwin's 

 conclusions on this matter are generally held to be essen- 

 tially true. It is obvious that his argument is capable of 

 further elaboration and development by additional know- 

 ledge, and always was regarded as being so by its author 

 and by every other competent person. But that is a 

 very different thing from holding Darwin's theory of 

 natural selection to be "inadequate." It is adequate, 



