When in the play does Proctor realize he is facing his own demise? How does he react to this? How does this match the characteristics of the tragic hero?

He realises his demise at the end of Act 3, and he reacts with asking Mary to testify for Elizabeth as he finally faces the consequences of his actions. This matches the tragic hero characteristics because he displays hubris (excessive pride) , Hamartia (an error that results in the downfall of said hero), Peripeteia (tragic consequences result of characters actions), Anagnorisis (the moment the hero realises their downfall)

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