424 OPHTHALMOLOGY 



and the mystery of heredity to survive and to repeople the earth, 

 have been such as were not so widely variant as to disqualify 

 their possessors for work and service; and the majority of their 

 children, those now living in the world, have eyes so near accuracy 

 in optical dimensions as to render their owners at least partly func- 

 tional in the evolution process. This almost infinitesimal variant of 

 Tj-1^ of an inch, the thickness of a sheet of paper, in eyeball measure- 

 ments may throw the unfortunate possessor out of the struggle 

 for existence, so far as perpetuation of the race goes, at least in 

 civilized life, and for some occupations, or it may render him a 

 most pathetic sufferer. I say it may do so, not that it does do this 

 invariably or generally. The simple law is that the greater the 

 ametropia the greater the certainty that it will do so, and the more 

 limited the range and choice of occupations. The lower, not the 

 positively lowest errors of refraction, however, in civilization are 

 those which in moral persons cause the greatest personal pain and 

 suffering. The high errors brutalize, immoralize, and exclude the 

 owner from most occupations; the lower cause pain and illness. 



Eye-strain is the unfortunate and inexpressive term that has come 

 into use for the results that follow the attempt of the eyes, brain, 

 and corelated organs to neutralize the defective function of the 

 optically imperfect eyeballs and mechanisms. The optical defect is 

 not morbid; it is at best pathogenic, secondarily or indirectly, 

 not primarily. Its secondary effect, the straining of physiologic 

 muscles and nerve-centres, is not in itself necessarily pathologic. 

 But it illustrates, and best illustrates, the great truth which text- 

 books, teachers, and medical science itself, are sadly prone to for- 

 get, that abnormal physiology is the origin of most pathology. 

 Unnatural action and over-action start the morbid function which 

 finally lands the physiologic upon the post-mortem table. To ignore 

 this truth is itself pathologic pathology; to scorn it is to add un- 

 scientific sin to the symptom-complex of the scientist's disease. It 

 is gratifying to find a reaction taking place the beginnings of it 

 at least. The magnificent paper of Dr. Putnam of Boston, read at 

 this Congress two days ago, is a hopeful sign of progress. I am sorry 

 he omitted the most striking illustrations of his thesis at his hand, 

 the production of headache, migraine, nervous, mental, digestional, 

 and scoliotic diseases, by eye-strain. The etiologic agency in these 

 cases is both organic and functional, according to the point of view, 

 but and for this he contended most warrantably it is pre- 

 eminently physiologic instead of anatomic, at least not in the 

 sense given that word by the pathologist of the past. The patho- 

 logist of the past has, indeed, completed his work. The great need 

 of the future is physiologic pathology. 



It should be noted that as eye-strain is itself simply functional, 



