In 1968, Robert Darnton published his first book, Mesmerism and the End of the Enlightenment in France, which established animal magnetism as a historiographical subject, and raised, magisterially, the question of the political influence of the doctrines of Mesmer on the eve of the Revolution. Fifty years later, the American historian revisits this pioneering study in an interview conducted on June 15, 2017 during his stay at the Institute of Advanced Studies in Paris. Responding to questions by Bruno Belhoste, Robert Darnton remembers his experience of writing his dissertation between Oxford and Paris, as well as his discovery of the phenomenon of animal magnetism and the French archives, and he discusses his methodology and his encounters with French historians.