EVOLUTIONARY TELEOLOGY. 367 



argue the necessity of every adaptation solely from 

 the fact that it exists," and that " we cannot mutilate 

 it grossly without injury to the function," we do not 

 " announce triumphantly that digestion is impossible 

 in any way but this," etc., but see equal wisdom and 

 no impugnment of design in any number of simpler 

 adaptations accomplishing equivalent purposes in low- 

 er animals. 



Finally, adaptation and utility being the only 

 marks of design in Nature which we possess, and 

 adaptation only as subservient to usefulness, the 

 Westminster Reviewer shows us how 



" The argument from utility may be equally refuted another 

 way. We found in our discussion of the mark of adaptation 

 that the positive evidence of design afforded by the mechan- 

 isms of the human frame was never accompanied by the possi- 

 bility of negative evidence. We regarded this as a suspicious 

 circumstance, just as the fox, invited to attend the lion in his 

 den, was deterred from his visit by observing that all the foot- 

 tracks lay in one direction. The same suspicious circumstance 

 warns us now. If positive evidence of design be afforded by 

 the presence of a faculty, negative evidence of design ought 

 to be afforded by the absence of a faculty. This, however, is 

 not the case." [Then follows the account of a butterfly, which, 

 from the wonderful power of the males to find the females at 

 a great distance, is conceived to possess a sixth sense.] " Do 

 we consider the deficiency of this sixth sense in man as the 

 slightest evidence against design? Should we be less apt to 

 infer creative wisdom if we had only four senses instead of 

 five, or three instead of four? No, the case would stand pre- 

 cisely as it does now. We value our senses simply because we 

 have them, and because our conception of life as we desire it 

 is drawn from them. But to reason from such value to the 

 origin of our endowment, to argue that our senses must have 



