76 DARWINIANA. 



I agree that, judging from tlie past, it is not im- 

 probable that variation itself may be hereafter shown 

 to resnlt from physical causes. When it is so shown, 

 yon may extend your necessity into this region, but 

 not till then. Bnt the whole course of scientific dis- 

 covery goes to assure us that the discovery of the 

 cause of variation will be only a resolution of varia- 

 tion into two factors : one, the immediate secondary 

 cause of the changes, which so far explains them ; the 

 other, an unresolved or unexplained phenomenon, 

 which will then stand just where the product, varia- 

 tion, stands now, only that it will be one step nearer 

 to the efficient cause. 



This line of argument appears to me so convincing, 

 that I am bound to suppose that it does not meet your 

 case. Although you introduced players to illustrate 

 what design is, it is probable that you did not intend, 

 and would not accept, the parallel which your supposed 

 case suggested. When you declare that the proof 

 of design in the eye and the hand, as given by Paley 

 and Bell, was convincing, you meaUj of coui'se, that 

 it was convincing, so long as the question was between 

 design and chance, but that now another alternative is 

 offered, one which obviates the force of those argu- 

 ments, and may account for the actual results without 

 design. I -do not clearly apprehend this third alter- 

 native. 



Will you be so good, then, as to state the grounds 

 upon which you conclude tliat the supposed proof of 

 design from the eye, or the hand, as it stood before 

 Darwin's theory was promulgated, would be invali- 

 dated by the admission of this new theory ? 



