THE ANTIQUITY OF DISEASES 269 



bronchitis, and, in its modified form, smallpox. All are more or 

 less exposed to scarlet fever, diphtheria, pneumonia, and influenza. 



444. We have historical evidence of the antiquity of many 

 diseases. Leprosy is mentioned in the Book of Exodus as pre- 

 valent in Egypt. By other accounts it was prevalent in India, 

 China, and Japan about the same time. Contagious diseases (e.g. 

 syphilis) were well known to the Greek and Roman writers. 1 We 

 have few accounts of them from the Middle Ages, when physicians 

 regarded their treatment as degrading to professional dignity ; but 

 at the Renaissance the ' great pox ' was a terrible scourge. " A 

 pox on you " was a common Elizabethan malediction. " Consump- 

 tion of the lungs may be traced with certainty in the writings of 

 every period as far back as the earliest attempts of the ancient 

 world to deal with medicine according to a method." 2 Granting 

 that diseases had not multiple origins, their wide prevalence in the 

 ancient world, when communities dwelt in far greater isolation 

 than at present, argues extreme antiquity. 



445. It seems probable that both man and his diseases arose 

 in the Eastern Hemisphere, where " behind dim empires ghosts of 

 dimmer empires loom." Still more ancient than the oldest 

 empires are the traces of the early agriculturists, who in turn were 

 preceded by the hunters and cave-men of the long Stone Ages. 

 Amongst savages of the lowest types the problem of the food- 

 supply is always acute. Population, as till lately amongst the 

 natives of Australia, tends always to exceed the available supply 

 and is limited by recurrent famine. Man is naturally a gregarious 

 animal, delighting in large communities, but the difficulty of pro- 

 curing sufficient food forces a race of hunters, not only to scatter, 

 but to assert rights of ownership over large areas of country, 

 intrusion into which by strangers is strongly resented. Hence 

 tribal jealousy, perpetual warfare, and frequently an isolation so 

 profound and stringent that the inhabitants of near valleys may be 

 of distinct types and speak a language unintelligible to their 

 neighbours. Civilization implies a dense and settled community, 

 which in turn implies a more abundant and secure supply of food, 

 and that, again, implies comparative peace, combined with regular 

 communications over great areas of land and even of water, where- 

 by the deficiencies of one part are supplied from the super- 



1 Hirsch's Handbook of Geographical and Historical Pathology, vol. ii. p. 2 

 (New Sydenham Society). The notion is general that the venereal diseases were 

 imported from America, but this would appear to be an error. 



2 Op. cit., vol. iii. p. 170- 



