Discuss dramatic irony in Twelfth Night and Othello.
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One of the most effective sorts of irony to find in a play is dramatic irony, since this involves the audience directly. As Enotes puts it, dramatic irony is:
the device of giving the spectator an item of information that at least one of the characters in the narrative is unaware of (at least consciously), thus placing the spectator a step ahead of at least one of the characters.
Deception often plays a crucial role in establishing dramatic irony, and in both Twelfth Night and Othello, it is key. In Othello, most of the dramatic irony (if not all) is a collusion between Iago and the audience, an irony that results in the most tragic of conclusions. In Twelfth Night, the dramatic irony is a result of Viola's appearance in Act I, scene iv as Cesario, a disguise she wears to the very last scene of the play. This dramatic irony is the crux of a great deal of comic mix-up.
In Othello, the events surrounding a lowly, but significant prop -- the handkerchief -- provide lots of dramatic irony. Shakespeare demonstrates his mettle as a dramatist here by creating key events of dramatic irony and suspense around a tangible item that the audience can see. From the moment that the handkerchief is dropped by Desdemona in Act III, scene iii and picked up by Emilia (Iago's wife), it begins a journey of deception that takes it from Emilia to Iago to Cassio to his mistress Bianca and back to Cassio again. Conspicuously, Desdemona is caught "red-handed" without the handkerchief by Othello and commits the only falsehood spoken by her in the play (it proves to be her complete undoing) when Othello asks her directly if she has lost it, she replies, "I say it is not lost." This small and humble hand prop provides tons of dramatic irony as the audience watches it passed from hand to hand, and is the key element in the play that seals Desdemona's fate at Othello's hands.
In Twelfth Night, it isn't a prop that provides the most significant dramatic irony, but another very theatrical device -- a costume. Viola decides in Act I, scene i to enter the world of Illyria dressed in her twin brother Sebastian's clothes, and she spends the balance of the play disguised as Cesario. The complications and dramatic irony that ensues from this are mostly to comic effect: Olivia's infatuation with Viola/Cesario, the duel that Viola must attempt to fight against Andrew, and, of course, all the mix-ups that occur once Sebastian arrives on the scene. However, Shakespeare manages to add poignancy to this ironic set-up, and this is most in evidence in the scenes between Viola (Cesario) and Orsino. Viola has fallen in love with the Duke, and her double-edged comments to him about love reveal and bittersweet perspective on love and longing. In Act II, scene iv, she has a poignant moment in which she reveals to Orsino what she knows of a woman's love by describing to the Duke a "daughter" of "father" who "lov'd a man" but "never told her love."
So, in Twelfth Night, not only does Shakespeare provide dramatic irony to boost the comic effect, he is able to utilize the dramatic irony of Viola's disguise to create and sweet and tender moments of revelation of feeling. While the dramatic irony in Othello leads to tragic consequences, in Twelfth Night, it builds much of the comic mistaken identity and also reveals to the audience the true nature of Viola's love.