C. Auguste Dupin discussing Dupin's method in the light of Charles Sanders Peirce's logic of making good guesses or "abductive reasoning," Nancy Harrowitz first quotes Poe's definition of analysis and then shows how "Poe the semiotician is running the gamut of possibilities here—inferences, reasoning backwards, visual, sensual and aural signs, reading faces. Playing cards with the man would have been an interesting experience." There is considerable controversy about the philosophical nature of Dupin's method. According to biographer Joseph Krutch, Dupin is portrayed as a dehumanized thinking machine, a man whose sole interest is in pure logic. However, Krutch has been accused elsewhere of
Charles Dupin and value of French exports and imports, with comparative figures for 1823, 1827 and 1834. In addition, he had a political career and was appointed to the Senate in 1852. His mathematical work was in descriptive and differential geometry. He was the discoverer of conjugate tangents to a point on a surface and of the Dupin indicatrix. Charles Dupin Baron Pierre Charles François Dupin (6 October 1784, Varzy, Nièvre – 18 January 1873, Paris, France) was a French Catholic mathematician, engineer, economist and politician, particularly known for work in the field of mathematics, where the Dupin cyclide and Dupin indicatrix