What, in literary terms, is an epiphany? Where do you see the epiphany happening in ? What is it that the narrator realizes about himself that causes him such "anger and angst"?

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James Joyce coined the literary term "epiphany"–he borrowed it from his Catholic upbringing and the season of Epiphan, In your own words, what, in literary terms, is an epiphany? Where do you see the epiphany happening in ? What is it that the narrator realizes about himself that causes him such "anger and angst"?