XVII THE METHOD OF ORGANIC EVOLUTION 347 



yet a provisional theory, founded upon incontrovertible 

 facts of nature, demonstrating a true cause for specific 

 modification, and affording a satisfactory explanation of 

 those countless phenomena of adaptation which every pre- 

 ceding theory had been powerless to explain. Further 

 consideration and discussion only increased the reputation 

 of the author and the influence of his work, which was 

 greatly enhanced by his Animals and Plants tender 

 Domestication, published nine years later ; and when this 

 had been fully considered — about twelve years after the 

 publication of the Origin — a large proportion of naturalists 

 in every part of the world, including many of the most 

 eminent, had accepted Darwin's views, and acknowledged 

 that his theory of Natural Selection constituted — to use 

 his own words — " the main but not the exclusive means 

 of modification." The effect of Darwin's work can only be 

 compared with that of Newton's Princiioia. Both writers 

 defined and clearly demonstrated a hitherto unrecognised 

 law of nature, and both were able to apply the law to the 

 explanation of phenomena and the solution of problems 

 wdiich had baffled all previous philosophers. 



Of late years, however, there has arisen a reaction 

 against Darwin's theory as affording a satisfactory ex- 

 planation of organic evolution. In America, especially, 

 the theories of Lamarck are being resuscitated as of equal 

 validity with natural selection ; while in this country, 

 besides a considerable number of Lamarckians, some 

 influential writers are introducing the conception of there 

 being definite positions of organic stability, quite in- 

 dependent of utility and therefore of natural selection ; 

 and that those positions are often reached by discontinuous 

 variation, that is, by spurts or sudden leaps of considerable 

 amount, which are thus " competent to mould races 

 without any help whatever from the process of selection, 

 whether natural or sexual."^ These views have been re- 

 cently advocated in an important work on variation,^ 



^ Discontinuity in Evolution. By Francis Galton. Mind, vol. iii., p. 

 367. 



- Materials for the Study of Variation^ treated loith especial regard to 

 Discontinuity in the Origin of Species. By William Bateson, M.A. 

 1894 (pp. XV. and 598). 



