The Evolution of Optics. 293 



a little affair of a hundred thousand years and she may lengthen the 

 eyeball a little in a healthy way, or, more properly and more probably, 

 will develop the MQller ring-fibers of the ciliary muscle to stand this 

 great task. But at present, so sudden has come the frightful strain 

 of civilization that there ensues a multitude of evils whose existence is 

 not a quarter suspected by the world, and only half suspected by the 

 medical profession. The great concealing, deceiving fact about eye- 

 strain is that the eye itself does not complain or suffer so much as 

 other organs. This fact makes every patient say : " My eyes are all 

 right ; do not pain me at all," and yet that same patient's life and 

 happiness may be destroyed by eye-strain. What is the reason of this 

 anomalous fact t These are three chief of many reasons : 1. Eye- 

 strain is due to no disease whatever, but to overuse and misuse of an 

 organ created for a different kind of use. 2. The enormous and pre- 

 ponderant importance of the function of vision to the life and welfare 

 of the organism makes Nature throw the brunt of the burden upon 

 other organs. If eyesight were ruined, then all is ruined ; other or- 

 gans, chiefly the nervous system, can afford to suffer better than the 

 eyes. 3. Healthy-looking eyes are the very essence of beauty; the 

 eyes are truly " the windows of the soul." Sexual selection has been 

 willing to sacrifice everything to maintaining pure, clear eyes, and has 

 therefore switched the morbid results of eye-strain to other parts 

 rather than mar the beauty of those superb structures. Hence the 

 creation of the great brood of reflex ocular neuroses. I am as con- 

 vinced as I am of my own existence that a great deal of the headache, 

 anorexia, dyspepsia, the reduced vitality, the hysteria, the neurasthe- 

 nia, the anaemia, the now morbidly exalted and now morbidly de- 

 pressed nervous energy, characteristic especially of the modern 

 woman, are due to the persistent influence of eye-strain. Of course, 

 whisky and corsets and laziness are also powerful causes. But the 

 worst about eye-strain is that it does not kill directly, but creates the 

 neurotic type, perverts and morbidizes the assimilative and nervous 

 systems, reduces healthy vitality, and manures the field for a prolific 

 crop of pathological weeds. 



DR. ROBERT G. ECCLES: 



While I agree with Dr. Gould that function precedes organism in 

 the processes of organic evolution. I am also a believer in the abso- 

 lutely mechanical structure of the universe. The introduction of the 

 psychological element does not abolish the necessity for the search for 

 efficient causes all along the line of biological development. I can 

 not see in what way the eye could have been evolved except as shown 

 by the speaker of the evening. There are purpose and intelligence 



