STRUGGLES NO PROOF OF TAIN. 333 



have shrunk in the living animal. Was this pain ? Clearly 

 not. It was clue to the iiritability of the muscular tissue. 



Another observation made over the dissectino-table is even 

 more instructive. One of my Tritons had been dead some 

 tunc, and was pinned down on a cork jjlate by the four 

 paws. I had taken out the heart and lungs, without exciting 

 any obvious contraction, when, on accidentally pricking the 

 tail with the scalpel, I was amazed to see it writhe ; repeating 

 the prick, my amazement increased as I saw the whole lower 

 extremities twist and writhe, so as to free the legs from the 

 pins which fastened them to the cork. A bystander would 

 have said that the animal must be suffering pain ; yet on 

 pricking the anterior extremities, the ribs, the stomach, and 

 the head, not a trace of sensibility could be detected. Dead 

 the animal assuredly was. He had been dead some hours 

 before I removed his heart, yet sensibility remained apparently 

 as active as ever in the tail ; and on examination I observed 

 this sensibility decreased as I ascended from the tail upwards, 

 disappearing altogether midway in the body. 



Up to this point, we have done little more than destroy 

 the value of the positive evidence which can be adduced in 

 support of the proposition that all animals feel pain. As 

 regards mere shrinking and struggling, fighting and crying, 

 we see that the evidence is null. If it should be said that 

 all animals possessing a nervous system must feel pain, 

 because pain belongs to the nervous system, I ask. To what 

 part of that system? We are certain that it does not 

 belong to every part. We have endless nerve-actions inces- 



