What is the Initial Incident and the Exposition in "The Case of Amontillado" and how are they different?"The Cask of Amontillado" by Edgar Allan Poe

What makes "The Cask of Amontillado" so intriguing is the
gothic horror that is created by the unreliable narrator who, among many aberrrant
behaviors, never explains to the reader what "the thousand injuries" of Fortunato
are. So, there is no true
"Initial Incident" in the exposition of Poe's narrative.  Therefore, too, the exposition
is incomplete since, by definition, it is "information essential to understanding the
work."

The exposition is also part of the rising action
which the initial incident is not.  This rising action occurs after Montresor flatters
Fortunato and induces the proud connosieur to examine his new cask of Amontillado.  For,
from this action the complication and turning points and denouement
follow.