In the theater, a speech of a character alone on stage, who thinks aloud and shows the audience what he does not say to the others.
In Othello
I have 't. It is engendered. Hell and night / Must bring this monstrous birth to the world's light.
Iago is alone on stage and speaks to the audience, with no one to deceive. In "It is begotten!" he reveals that the plan against Othello is already ready, something he would not tell any other character.
Act I: Venice, the night accusation and the Senate hearing, Iago
And out of her own goodness make the net / That shall enmesh them all.
Act II: Cyprus, the storm and Cassio's fall, Iago
Trifles light as air / Are to the jealous confirmations strong / As proofs of holy writ.
Act III: The temptation and the handkerchief, Iago
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