Ye Tianshi; ca 1690-1760 A.D. - Ye is famous for his thesis on febrile diseases, in which he postulated transmission of the disease through four stages: wei, qi, ying, and blood. His book Wenre Lun (Treatise on Epidemic Fevers) published in 1746, was followed up by an even more famous book Wenbing Tiaobian (Detailed Analysis of Febrile Diseases) in 1798, using this four stage system as its basis.