Toward a Definition of Opera

By looking at Aristotle the article looks to determine if Opera is music or dramatic poetry. I found the answers to the guided questions as follows.
The purpose of music in the realm of drama is to help express a situation or crisis by imitating feeling.
The classical theory of imitation argues that as the article says "3 forms of art based on 3 possible objects of imitation: nature, feeling, and action" exists. Dramatic poetry falls into both feeling and action.
Aristotle's Poetics state that the difference between comedy and tragedy is the nature of emotions aroused. Tragedy's emotions are pity and fear versus Comedy's laughter and charm.
The difference in music and poetry is the presentation of an aspect. In music the aspect is human feeling where poetry is the presentation of an aspect of action.
Drama when believable pulls the audience in and creates feelings. If it is not believable the audience no longer cares about the piece, emotion will not be aroused and the audience loses interest.
Catharsis is a purging of emotion. "Catharsis of aroused emotion" is when the audience senses meaning in a work of dramatic art.
At the end of the article it is decided that opera is a form of dramatic poetry that uses music to achieve catharsis.