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
The Invisible Detective a darkened room. In fact, Brandon Lake does not exist; he was invented by the four children, who investigate all his cases themselves. Art plays the Invisible Detective in weekly sessions held in a darkened room, during which the Detective addresses the concerns of local residents, in exchange for a small fee. Each book also has a parallel subplot set in the 2000s, where Art's grandson, also named Art, and his friend Sarah have related mysteries to solve. The titles in the series are: The series revolves around the cases of eponymous detective, Brandon Lake. The books' protagonists are the