C. Auguste Dupin implies "duping" or deception, a skill Dupin shows off in "The Purloined Letter." Detective fiction, however, had no real precedent and the word "detective" had not yet been coined when Poe first introduced Dupin. The closest example in fiction is Voltaire's "Zadig" (1748), in which the main character performs similar feats of analysis, themselves borrowed from "The Three Princes of Serendip", an Italian rendition of Amir Khusrau's Hasht Bihisht. In writing the series of Dupin tales, Poe capitalized on contemporary popular interest. His use of an orangutan in "The Murders in the Rue Morgue" was inspired by the popular reaction
Dupin indicatrix Dupin indicatrix In differential geometry, the Dupin indicatrix is a method for characterising the local shape of a surface. Draw a plane parallel to the tangent plane and a small distance away from it. Consider the intersection of the surface with this plane. The shape of the intersection is related to the Gaussian curvature. The Dupin indicatrix is the result of the limiting process as the plane approaches the tangent plane. The indicatrix was invented by Charles Dupin. For elliptical points where the Gaussian curvature is positive the intersection will either be empty or form a closed curve. In the