6  JELLY-FISH, STAR-FISH, AND SEA-URCHINS. 
feel that it is desirable to touch before proceeding 
to give an account of my experiments, and this has 
reference to the vivisection which many of these 
experiments have entailed. But in saying what 
I have to say in this connection I can afford to be 
brief, inasmuch as it is not needful to discuss the 
so-called vivisection question. I have merely to 
make it plain that, so far as the experiments which 
IT am about to describe are concerned, there is not 
any reasonable ground for supposing that pain can 
have been suffered by the animals. And this it is 
easy to show; for the animals in question are so low 
in the scale of life, that to suppose them capable 
of conscious suffering would be in the highest 
degree unreasonable. Thus, for instance, they are 
considerably lower in the scale of organization than 
an oyster, and in none of the experiments which 
I have performed upon them has so much laceration 
of living tissue been entailed as that which is 
caused by opening an oyster and eating it alive, 
after due application of pepper and vinegar. There- 
fore, if any one should be foolish enough to object 
to my experiments on the score of vivisection, a 
fortiori they are bound to object to the culinary 
use of oysters. Of course, it may be answered to 
this that two blacks do not make a white, and that 
- I have not by this illustration succeeded in proving 
my negative. To this, however, I may in turn 
reply that, for the purpose of morally justifymg my 
experiments on the ground which I have adopted, 
it is not incumbent on me to prove any negative; 
it is rather for my critics to prove a positive. That 
