THE DOCTRINE OF FINAL CAUSES. 507 



fact, the assumption of an end or purpose in the 

 structure of organized beings, appears to be an 

 intellectual habit which no efforts can cast off. It 

 has prevailed from the earliest to the latest ages 

 of zoological research ; appears to be fastened upon 

 us alike by our ignorance and our knowledge ; and 

 has been formally accepted by so many great ana- 

 tomists, that we cannot feel any scruple in believ- 

 ing the rejection of it to be the superstition of a 

 false philosophy, and a result of the exaggeration 

 of other principles which are supposed capable of 

 superseding its use. And the doctrine of unity of 

 plan of all animals, and the other principles asso- 

 ciated with this doctrine, so far as they exclude the 

 conviction of an intelligible scheme and a discover- 

 able end, in the organization of animals, appear 

 to be utterly erroneous. I will offer a few reasons 

 for an opinion which may appear presumptuous in 

 a writer who has only a general knowledge of the 

 subject. 



1. In the first place, it appears to me that the 

 argumentation on the case in question, the sepia, 

 does by no means turn out to the advantage of the 

 new hypothesis. The arguments in support of the 

 hypothetical view of the structure of this mollusc 

 were, that by this view the relative position of the 

 parts was explained, and confirmations which had 

 appeared altogether anomalous, were reduced to 

 rule ; for example, the beak, which had been sup- 

 posed to be in a position the reverse of all other 



