The Senses and the Nervous System 119 



happier by laughing, sadder by weeping — then the poor fish 

 has no emotions comparable to ours, for he can neither laugh 

 nor weep. However, there are some feelings which he can 

 express. He can express hunger by searching for food. He 

 can express anger by expanding his fins and gill covers and 

 attacking his enemy. He can express love by pursuing the 

 female of the species. He may also have other ways of ex- 

 pressing his feelings, and one, at least, we can understand, 

 because we sometimes use it ourselves: flight from what he 

 fears. 



Pain seems to be an instrument which nature has devised 

 for the preservation of the individual. What tends to destroy 

 hurts, and is avoided. If putting your hand on a hot stove 

 brought no pain, but only a sizzling sound, a little smoke, 

 and a faintly appetizing odor, you would not be nearly so 

 expert in avoiding burns as you are. By the same token, if it 

 did not hurt a fish when another fish ate it, that fish would 

 not be nearly so desirous of avoiding the experience as it 

 actually is. Why does a Siamese fighting fish dart aside each 

 time it is bitten by its opponent in a fight, if the bite does 

 not give it pain? 



All of the foregoing is obvious, and yet many people, of 

 whom I am one, shrink from killing a deer, but have no 

 scruples about the often more lingering death which they 

 inflict on a trout. They like to tell themselves that it is 

 because the fish cannot feel pain, while the real reason is 

 that the fish, regardless of what it feels, cannot express pain. 

 If every trout were to scream unceasingly as long as it had a 

 hook in its mouth, trout-fishing would be a nerve-shattering 

 experience which few of its present devotees could undergo 

 more than once. 



However, in defense of the fisherman, I find two reasons 

 for believing that the fish's suffering is, comparatively speak- 

 ing, slight. One is that the actual sensation of pain is appar- 



