Pierre Duhem

Pierre Duhem (Paris, 1861 - Cabrespine, 1916) was a French theoretical physicist, philosopher of science and historian of medieval science. He is counted among the founders of physical chemistry, and his name is attached today to several thermodynamic equations, among them the Gibbs-Duhem equation. He matters above all for his critique of the idea of the crucial experiment and for his pioneering studies of medieval science.

Born into a devout and conservative Catholic family, he trained at the École normale supérieure in Paris in mathematics and physics. His doctoral work on the thermodynamic potential in electrochemical cells openly challenged the principle of maximum work championed by Marcellin Berthelot. The clash, both scientific and political, is traditionally said to have damaged his career. After posts in Lille and Rennes he settled as professor of theoretical physics at Bordeaux, where he remained for the rest of his life.

Duhem was a supporter of energetics, the view that physical phenomena could be derived from the principles of thermodynamics. He did not manage to reduce electromagnetism to that framework, and he distrusted atoms as established physical reality, which put him at odds with the statistical mechanics of Maxwell and Boltzmann. He also opposed Einstein's theory of relativity.

In The Aim and Structure of Physical Theory (1906) he argued that hypotheses are never tested in isolation: what faces experience is a whole interlocking set of hypotheses and background assumptions. The Duhem-Quine thesis that follows means that a failed prediction cannot be pinned with certainty on one particular claim. This idea anticipates what is now called confirmation holism.

He was also a pioneer in the study of medieval science. In his ten-volume The System of the World he argued that thinkers such as Buridan, Oresme and Roger Bacon anticipated many ideas later credited to Galileo, and that the medieval Church had helped foster Western science, against the Enlightenment view of the Middle Ages as barren. His influence today reaches the philosophy of science, the history of physics and debates about the role of theory in experiment.