440 [ OPHTHALMOLOGY 



to transmit to brain, to manufacture sensation, to dominate all 

 other cerebral function, instigate and direct all motion where 

 is the end of the marvelous task! The end is in failure to do any 

 one of these things, and to make that inch-in-diameter eyeball of 

 a spheric perfection which shall not vary by ^-^ of an inch from 

 the norm. The end is not to have prevented conjunctivitis, trau- 

 matism, keratitis, iritis, glaucoma, cataract, retinitis, and other 

 multiform diseases, prone especially to occur in the astoundingly 

 complex and refined organism. The pathology of animalian evo- 

 lution has therefore been in large part the pathology of vision. 

 The organism otherwise perfect, except as to an infinitesmal visual 

 part, is thrown out by this optical necessity. The mechanism par 

 excellence of the exclusion of the unfit is thus made clear. 



And to this now add the consummating and crowning function 

 of vision, the creation of intellect. Psychology, history, and 

 biology unite to demonstrate that the objectivation of the i/^x>? of 

 civilization is almost uniquely by means of vision. The greatest 

 task of all human history was the creation of the letters of the 

 alphabet. It was so difficult that only one race did it, and within 

 one or two millenniums all others have come to a knowledge and use 

 of civilization only through the adoption of the invention. No 

 writing and printing, no civilization. But the letters of the alpha- 

 bet are conventionalized symbols of pictures or things seen. Add 

 to this that language itself is of identic origin. There has been no 

 speech except to express the result of ocular function. Almost all 

 psychology is summarized as handlings, coordinations, and deduc- 

 tions of visual images, of these and of the motions made possible 

 by sight. Thus every cerebral function, perception, apperception, 

 feeling most of it, and willing, that which is effective, surely 

 reasoning and judgment, all spring originally and constantly, 

 are bound up with, dependent upon, and interdependent with 

 vision. 



There is something more than mere imagery and fancy which 

 analogizes the course and phases of these developmental stages to 

 the way of water-flow in the world. Decidedly optical are the sun, 

 cloud, rainfall, and snowfall upon the uplands and mountains whence 

 spring the crystal streams and rivulets of physiology. In them 

 optics becomes function and action, physics becomes physiologies. 

 The lower falling brooks become discolored and morbid when they 

 reach the homes and degradations of man, physiology becomes 

 pathology. But the stream broadens into the large river of biology 

 with the commerce, the health and unhealth of a continent, until 

 finally the Mississippi sweeps to the mothering ocean of sociology 

 where sail and steam the navies of the world. 



Thus all routes and efforts lead to man, and all biology ends in 



