1787-1872

French Physician and Statistician

Pierre Charles Alexandre Louis is best known for an approach to medicine known as the "numerical system." Louis's admirers credited him with establishing medicine as an exact science by demonstrating the value of the statistical method in diagnostics and therapeutics. Louis's meticulous work on tuberculosis and typhoid fever provided statistical studies of the major symptoms of the diseases and the postmortem lesions associated with them. By systematically testing the effectiveness of therapeutic phlebotomy, Louis demonstrated that the timing and quantity of bloodletting had no impact on the course or mortality of the diseases for which it was commonly employed.

The son of a vineyard keeper, Louis grew up in the Champagne region of France. After a few years of law school, he became interested in medicine and studied at Rheims and Paris. He was awarded the M...