In New York City Dr. Cronin finds that over 30 per cent, of the school children are suffering from the gross forms of defective eyesight. It must be remembered that the worst defects are not included in these statistics.
Lastly, the greatest of the misfortunes which may be traced to this cause are those connected with intellectual progress, the literary workers being those who suffer most. In direct and indirect ways the advances of civilization are most frequently conditioned upon use of the eyes in writing and reading. Certainly one half or more of the great writers and thinkers of the world have had their lives turned into tragedies of personal affliction by this unsuspected cause. The biographies of Swift, Nietzsche, Parkman, George Eliot, the Carlyles, Whittier, Darwin, Wagner, Taine, Symonds, Heine, De Quincey, Huxley, Lewes, Margaret Fuller, Jules Verne, de Maupassant, Balzac, Berlioz and many others are filled with pathetic evidences of the truth. It is noteworthy that in the monumental 'Life of Wagner' Dr. Ellis, who is at once physician, musician and biographer, after exhaustive research, confirms the theory that eyestrain was the chief cause of the poignant physical sufferings of that great genius. And what influences such afflictions have on the character of the men and of their works only the discerning can surmise. The large majority of the men and women mentioned above have a striking likeness as regards a certain harshness, even bitterness, and a peculiar and pitiless insistence on logical distinctions; all but one or two were pessimistic and unreligious. Only art saved Wagner from an acerbity and skepticism, illustrated by his enemy-friend Nietzsche and his philosopher, Schopenhauer. It does not require a great mind to recognize the profound influence of disease upon character and philosophy.