Born in
Lyon, Desargues came from a family devoted to service to the French crown. His father was a royal
notary, an investigating commissioner of the
Seneschal's court in Lyon (1574), the collector of the
tithes on ecclesiastical revenues for the city of Lyon (1583) and for the
diocese of Lyon. Girard Desargues worked as an
architect from 1645. Prior to that, he had worked as a tutor and may have served as an engineer and technical consultant in the entourage of
Richelieu. Yet his involvement in the Siege of La Rochelle, though alleged by Ch. Weiss in
Biographie Universelle (1842), has never been testified. As an architect, Desargues planned several private and public buildings in Paris and Lyon. As an engineer, he designed a system for raising water that he installed near Paris. It was based on the use of the
epicycloidal wheel, the principle of which was unrecognized at the time. His research on perspective and geometrical projections can be seen as a culmination of centuries of scientific inquiry across the classical epoch in optics that stretched from al-Hasan
Ibn al-Haytham (
Alhazen) to Johannes
Kepler, and going beyond a mere synthesis of these traditions with Renaissance perspective theories and practices. His work was rediscovered and republished in 1864. A collection of his works was published in 1951, and the 1864 compilation remains in print. One notable work, often cited by others in mathematics, is "Rough draft for an essay on the results of taking plane sections of a cone" (1639). Late in his life, Desargues published a paper with the cryptic title of
DALG. The most common theory about what this stands for is
Des Argues, Lyonnais, Géometre (proposed by
Henri Brocard). He died in Lyon. == See also ==