pgronk at 2013-10-06 18:39:44:
I think there are many intriguing facets and implications to the concept of reversal in drama (and to the real life it imitates). It certainly entails a dramatic change in circumstance, fortune or relationship.
But for Aristotle reversal, peripeteia, also meant a reversal of something else rife with paradox and irony: the reversal of intention. That is, a character acts in order to obtain or effect one result -- and gets the exact opposite.
The classic example in Greek tragedy is, once again, Aristotle's model play, "Oedipus the King": the actions Oedipus takes to defeat the prophecy that he would kill his father and marry his mother, guarantee that he will fulfill the prophecy. His best intentions seal his fate.
Freud took away from the Oedipus tragedy that murder and incest are universal impulses embedded in the unconscious human psyche --- well for half of humanity, anyway, men. Jung had another takeaway from it and similar myths: "Every psychological extreme secretly contains its own opposite or stands in some sort of intimate and essential relationship to it...the more extreme a position is the more easily we may expect an enantiodromia, a conversion of something into its opposite. The best is most threatened with some devilish perversion just because it has done the most to suppress evil." (Symbols of Transformation)
Or as the saying goes: "The road to hell is paved with good intentions."