Nicolas Claude Fabri de Peiresc (1580‐1637) and the lost humanism

Peiresc [1580-1637], councillor in the parliament of Aix-en-Provence (France), exchanged voluminous correspondence with many scholars in Europe, including Galileo and the Lincei. He carried out, with his friend Gassendi, researches on astronomy, geology and anatomy. Peiresc’s writings on eye and vision are preserved in an unpublished manuscript of 980 pages, kept in the library of Carpentras (France). They include letters to Luilier, Bourdelot, Gassendi and Schikard, and contain several minutes of dissection of eyes from various animals (eagle, whale, cat, owl, seal and chameleons) carried out in 1634, as well as Peiresc’s observations on his own view. Peiresc also undertook experiments that consisted in removing the eye lens or replacing it with glass lenses, so as to establish the course of light rays in the eye under observation. As the images formed on the retina are upside down compared to the original object, Peiresc imagined that the retina was not the sensitive organ of vision but acted as a mirror, the image being captured on the back side of the lens. These studies precede Descartes’ Dioptrique (1637) and postdate Plempius’ Ophthalmographia (1632); they were not published, so they remain until today almost ignored.