575.8 115 



V. 



Lyell and Lamarckism : a Rejoinder. 



IF the author of " Lyell and Lamarckism : a Reply to Professor 

 W. K. Brooks" (Natural Science, May, 1896), means, by the 

 words " an explanation," on p. 331, a complete and ultimate explana- 

 tion, I fully agree with him that, in this sense of the words, natural 

 selection is no explanation of the attributes of living things, and'that, 

 " we should still want to know the true causes of them," although the 

 fact that we " want to know " is no evidence that we ever shall know 

 the true cause, vera causa, of anything. 



Explanations, although imperfect, may still be valuable, even if 

 we are never to find out " that which produceth a thing and maketh 

 it what it is." 



If it should ever be proved, as it may for all I know, that the 

 matter which composes the known universe has been sifted out from 

 other forms of matter by its property of weight, gravitation would 

 remain as good an explanation of our " universe " as it is now, 

 although we should still " want to know" how our particular sort of 

 matter got its weight. 



Darwin's work, like all good work in science, is an attempt to 

 find out a little of the order, as distinguished from the true cause, of 

 nature. It is a highly successful effort to study the history of living 

 things, by means of all available evidence ; and, as I understand it, 

 the value of natural selection is quite independent of whatever we 

 may discover, or fail to discover, concerning the true cause of that 

 diversity among individuals which has, by an unfortunate use of 

 words, come to be called variation. 



The author of the article on " Lyell and Lamarckism " says : 

 " According to the Lamarckian view, all adaptations, at any rate all 

 adjustments concerning whose action and efficacy there is no dispute, 

 have arisen in the same way as the enlargement of a muscle by exer- 

 cise " (p. 330); that is, "they must be ascribed to a fundamental 

 property of protoplasm " (p. 328); "and the assertion that structural 

 adjustments for rendering them possible exist in organisms is just 

 what Lamarckians contend. Therefore on this point Brooks agrees 

 with Lamarckians ; but whereas he supposes that these structural 

 adjustments have to be explained, Lamarckians believe that they 

 are merely thejundamental properties of protoplasm " (p. 330). 



