Two Hundred Circling Years
Or will likely ever produce -- it's just awfully hard to imagine a single writer who revolutionizes one genre (horror), creates another (mystery fiction), and does A-list work in four more (science fiction, satire, humor, and hoax), while also adding substantially to the poetic canon and re-inventing literary criticism. (Maybe this year I'll get a copy of the Complete Essays to go with the Complete Poems and Tales.)
The great thing about Poe is not just his polymathic talent (and I haven't even covered his cryptographical, philosophical, or scientific work, which is considerably better than mere dilettantism) but the way all his manias and wonders seem to fit together, clues in some great Dupinesque puzzle, characters in a big Gold-Buggy cipher. His mysteries are "studies of ratiocination," like the codes and the SF, but his SF uses the same symbolic language as his horror, which implies (as does, say, Eureka) that the two are both sides of the same coin of understanding, which coin might better be expressed as something akin to "initiation" or "mysticism" or "illumination." Poe is his own great chain of being, his own Palace of Memory (stalked by the Red Death, or imploding into the tarn as it may be), which is itself a code to ratiocinative processes.
And then, as you're getting ready to take it all too seriously, there is the cosmic joke that is Poe's life story -- a humor as black and bleak as "Hop-Frog" or "Metzengerstein." The father of mysteries dies of unknown causes after a three-day disappearance; the ratiocinator and critic willingly embraces Lethe and Nepenthe. The poet inspired by "the death of a beautiful woman" has a life haunted by his young wife's death; the would-be Southern aristocrat must become a New York money-grubber; the hoaxer and student of revenge has his reputation ruined by his own literary executor's posthumous lies; the great exponent of unified effect leaves his only novel unfinished. (Or is it? I re-read Pym for my Weird Tales column on Antarctica, and I begin to strongly suspect that the "unfinished" ending is exactly how Poe intends the work to end.)
Poe is not "his own greatest creation" -- most of the various "Edgar A. Poe"s that he tried to create were one or another type of vainglorious, over-dramatizing stiff. The actual Poe is, it seems to me, the unwitting hero of a Poe story ("the play is the tragedy, Man") who denies his own fate while you watch it rush upon him. In his shudder-tales, Poe intends (among other things) for the reader to respond to the tale like a hypochondriac studying a medical text -- every symptom that appears in the narrator triggers an uncomfortable recognition (real or illusory) in the reader. As you read a Poe story, you increasingly fall into the trap Poe lays for you -- you wind up doubting the rationality of anyone who claims that the story is unreal. "I do not dream! I am not mad!" says the narrator. And you respond by gleefully falling into the folie a deux. Every reader of Poe is like the traveler listening to Roderick Usher -- and then listening with Roderick Usher.
It's all descents into the Maelstrom; grab a barrel and hang on until you die.