PART III 



THE VISION OF TROUT 



I 

 A PRELIMINARY CAST 



In a well-known Greek myth, Semele, one of Jove's many 

 mistresses, is presented as having persuaded her lover to 

 reveal himself to her in his Olympian majesty, and as having 

 been burned to a cinder in the conflagration ; — the moral of 

 this being that man is not intended to see things as they are, 

 but only in such form and to such extent as is good for him. 

 This is, I believe, in full accord with the views of modern 

 science, which holds that man sees nothing absolutely as it is, 

 but only relatively and as is necessary for the purposes of 

 his being. Even so his perception of things seen is not the 

 sole result of the image on the retina, but is a subjective 

 effect produced upon the mind by the combination of the 

 image and the results of experience gained through the sense 

 of touch and possibly other senses connecting and co- 

 ordinating the image thrown upon the retina. A baby, it is 

 supposed, sees everything flat at first. He has to feel his way 

 through his sense of touch to a sense of distance and per- 

 spective. Man's eye therefore is not in the absolute sense a 

 perfect organ, but only relatively perfect for the purposes 

 of the needs and nature of man. 



I do not think that, if this proposition be true of man, 

 it can be any less true of fish, and, in considering the way of 



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