 pierre-charles-alexandre louis (14 april 178722 august 1872) was a french physician, clinician and pathologist known for his studies on tuberculosis, typhoid fever, and pneumonia, but louis's greatest contribution to medicine was the development of the "numerical method", forerunner to epidemiology and the modern clinical trial. ==biography== louis was born in ay, champagne, the son of a wine merchant. he grew up during the french revolution and initially thought to study law, later switching to medicine, graduating in 1813. his initial studies were in reims, but he completed them in paris. louis married late in life, having a single son (armand) who died of tuberculosis while still a boy in 1854, and louis retired from medical practice the same year. charles sumner, who visited louis and observed him teaching at the hÃ´tel-dieu de paris, described him as "a tall man, with a countenance that seems quite passive."{{cite book | author= pierce el | title = memoir and letters of charles sumner | pages =
1787_births 1872_deaths