Irony of the perverse
The narrator states that under the influence of the Imp, people do things because they know they shouldn't. In other words, "through its promptings, we act, for the reason that we should not". The narrator himself calls this a "paradoxical something." As such, people knowing they shouldn't do something ironically makes them want to do something.
Irony of the narrator
Although the narrator at first presents himself as being reasonable, he later admits that he is a murderer. He says that he does not want to reader to "fancy [him] mad," but ironically presents himself as being completely mad.
Irony of reason
In asserting his point, Poe states that "In theory, no reason can be more unreasonable; but, in fact, there is none more strong". As such, the thing that ironically seems unreasonable is actually the most reasonable, according to the narrator.
