Tales of Ratiocination (Detective Fiction) by Poe

Part of the genius of Edgar Allan Poe is that he exceeded in a number of different types of endeavors. In addition to his reputation as a poet, his originality in his literary criticisms, and the perfection he achieved in creating gothic tales of terror and science fiction, he is also acknowledged as the originator of detective fiction. Poe invented the term "Tale of Ratiocination." The ratiocination, however, is not just for the detective; Poe does not allow the reader to sit back and merely observe; the process of ratiocination which he sets up is also intended for the reader, as well as for the detective. In fact, the story becomes one in which the reader must also accompany the detective toward the solution and apply his own powers of logic and deduction alongside those of the detective. This idea becomes very important in all subsequent works of detective fiction. That is, in all such fiction, all of the clues are available for the reader, as well as the detective, to solve the crime (usually murder), and at the end of the story, the reader should be able to look back on the clues and realize that he could have solved the mystery. A detective story in which the solution is suddenly revealed to the reader is considered bad form. Poe, then, introduces one of the basic elements of the detective story — the presentation of clues for his readers, and in addition to the above, Poe is also credited with introducing and developing many other of the standard features of modern detective fiction.
For example, M. Auguste Dupin is the forerunner of a long line of fictional detectives who are eccentric and brilliant. His unnamed friend, who is a devoted admirer of the detective's methods, is less brilliant but, at times, he is perhaps more rational and analytical than Dupin is. He never, however, has the flashes of genius that the detective exhibits; instead, he begins the tradition of the chronicler of the famous detective's exploits — that is, he mediates between reader and detective, presenting what information he has to the reader, while allowing the detective to keep certain information and interpretations to himself. This technique has since been employed by numerous writers of detective fiction, the most famous being the Sherlock Holmes and Dr. Watson combination. Almost as popular are the well-known novels of Rex Stout, dealing with the eccentric Nero Wolfe and his sidekick, Archie Goodwin, further examples of Poe's methodology. In all the cases that these detectives attempt to solve, the eccentric detective has a certain disdain, or contempt, for the police and their methods, and this has also become a standard feature of many detective stories, along with the fact that the head of the police force feels, as he does in "The Murders in the Rue Morgue," that this amateur detective, while solving the murder, is a meddler.
Poe is clearly responsible for and should be given credit for giving literature these basics of the detective story as a foundation for an entirely new genre of fiction: (1) the eccentric but brilliant amateur sleuth; (2) the sidekick, or listener, or worker for the clever detective; (3) the simple clues; (4) the stupidity or ineptitude of the police; (5) the resentment of the police for the amateur's interference; and (6) the simple but careful solution of the problem through logic and intuition.

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