Pierre Duhem 1861 – 1916

Pierre Duhem was a French theoretical physicist, philosopher of science, and historian of medieval science. His work in thermodynamics and chemistry was respected during his lifetime, but his most enduring influence has been philosophical and historical. The Aim and Structure of Physical Theory defended a conventionalist account of physical theory and articulated what is now called the Duhem-Quine thesis: that no isolated hypothesis can be tested in isolation, since every test brings down a whole interconnected body of auxiliary assumptions. His ten-volume Système du monde rescued medieval natural philosophy from neglect.

Pierre Maurice Marie Duhem was born in Paris in June 1861 to a Catholic family from Roubaix. He entered the École Normale Supérieure in 1882, took the agrégation in physics, and in 1884 submitted a doctoral thesis on the thermodynamic potential that was rejected on political grounds by Marcellin Berthelot, whose chemical theories Duhem had attacked. A second thesis was accepted at Lille in 1888, and from 1894 he held the chair of theoretical physics at the University of Bordeaux, where he remained for the rest of his career, producing both fundamental work in thermodynamics and continuum mechanics and a vast body of writing in the history and philosophy of science.

His scientific works include the Traité de mécanique chimique (1897–1899), Thermodynamique et chimie (1902), and Le Mixte et la combinaison chimique (1902); his philosophical and historical works the celebrated La Théorie physique: son objet, sa structure (1906), Sauver les phénomènes (1908), Études sur Léonard de Vinci (three volumes, 1906–1913), and the immense Le Système du monde (ten volumes, 1913–1959, the last five appearing posthumously).

Duhem defended a moderate instrumentalism on which physical theory aims at simple, lawful representation rather than metaphysical truth and articulated the thesis — refined by Quine half a century later — that no scientific hypothesis is tested in isolation from the auxiliary assumptions that join it to experiment. His historical recovery of the medieval Parisian natural philosophers Buridan and Oresme inaugurated the modern study of medieval science. He died at Cabrespine in September 1916.